Headgear tubing for a patient interface

ABSTRACT

A patient interface for treating sleep disorder breathing includes a textile tube that also provides support for the seal forming structure. The textile tube includes an inner and outer layer that are joined along seams to form an air chamber or passageway. The textile tube can be pre-shaped so that the textile tube resiliently returns to a pre-determined shape prior to the introduction of pressurized air.

1 CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of Australian ProvisionalApplication Nos. 2019902290, filed Jun. 28, 2019, and 2019902316, filedJun. 30, 2019, each of which is hereby incorporated herein by referencein its entirety.

The disclosures of International Application Nos. PCT/AU2019/050655,filed Jun. 25, 2019, and PCT/IB2020/051079, filed Feb.11, 2020, are eachincorporated herein by reference in its entirety.

A portion of the disclosure of this patent document contains materialwhich is subject to copyright protection. The copyright owner has noobjection to the facsimile reproduction by anyone of the patent documentor the patent disclosure, as it appears in Patent Office patent files orrecords, but otherwise reserves all copyright rights whatsoever.

2 BACKGROUND OF THE TECHNOLOGY 2.1 Field of the Technology

The present technology relates to one or more of the screening,diagnosis, monitoring, treatment, prevention and amelioration ofrespiratory-related disorders. The present technology also relates tomedical devices or apparatus, and their use.

Certain forms of the present technology relate to patient interfacesused in the treatment of respiratory, prevention and amelioration ofrespiratory-related disorders.

2.2 Description of the Related Art 2.2.1 Human Respiratory System andIts Disorders

The respiratory system of the body facilitates gas exchange. The noseand mouth form the entrance to the airways of a patient.

The airways include a series of branching tubes, which become narrower,shorter and more numerous as they penetrate deeper into the lung. Theprime function of the lung is gas exchange, allowing oxygen to move fromthe inhaled air into the venous blood and carbon dioxide to move in theopposite direction. The trachea divides into right and left mainbronchi, which further divide eventually into terminal bronchioles. Thebronchi make up the conducting airways, and do not take part in gasexchange. Further divisions of the airways lead to the respiratorybronchioles, and eventually to the alveoli. The alveolated region of thelung is where the gas exchange takes place, and is referred to as therespiratory zone. See “Respiratory Physiology”, by John B. West,Lippincott Williams & Wilkins, 9th edition published 2012.

A range of respiratory disorders exist. Certain disorders may becharacterised by particular events, e.g. apneas, hypopneas, andhyperpneas.

Examples of respiratory disorders include Obstructive Sleep Apnea (OSA),Cheyne-Stokes Respiration (CSR), respiratory insufficiency, ObesityHyperventilation Syndrome (OHS), Chronic Obstructive Pulmonary Disease(COPD), Neuromuscular Disease (NMD) and Chest wall disorders.

Obstructive Sleep Apnea (OSA), a form of Sleep Disordered Breathing(SDB), is characterised by events including occlusion or obstruction ofthe upper air passage during sleep. It results from a combination of anabnormally small upper airway and the normal loss of muscle tone in theregion of the tongue, soft palate and posterior oropharyngeal wallduring sleep. The condition causes the affected patient to stopbreathing for periods typically of 30 to 120 seconds in duration,sometimes 200 to 300 times per night. It often causes excessive daytimesomnolence, and it may cause cardiovascular disease and brain damage.The syndrome is a common disorder, particularly in middle agedoverweight males, although a person affected may have no awareness ofthe problem. See U.S. Pat. No. 4,944,310 (Sullivan).

Cheyne-Stokes Respiration (CSR) is another form of sleep disorderedbreathing. CSR is a disorder of a patient's respiratory controller inwhich there are rhythmic alternating periods of waxing and waningventilation known as CSR cycles. CSR is characterised by repetitivede-oxygenation and re-oxygenation of the arterial blood. It is possiblethat CSR is harmful because of the repetitive hypoxia. In some patientsCSR is associated with repetitive arousal from sleep, which causessevere sleep disruption, increased sympathetic activity, and increasedafterload. See U.S. Pat. No. 6,532,959 (Berthon-Jones).

Respiratory failure is an umbrella term for respiratory disorders inwhich the lungs are unable to inspire sufficient oxygen or exhalesufficient CO₂ to meet the patient's needs. Respiratory failure mayencompass some or all of the following disorders.

A patient with respiratory insufficiency (a form of respiratory failure)may experience abnormal shortness of breath on exercise.

Obesity Hyperventilation Syndrome (OHS) is defined as the combination ofsevere obesity and awake chronic hypercapnia, in the absence of otherknown causes for hypoventilation. Symptoms include dyspnea, morningheadache and excessive daytime sleepiness.

Chronic Obstructive Pulmonary Disease (COPD) encompasses any of a groupof lower airway diseases that have certain characteristics in common.These include increased resistance to air movement, extended expiratoryphase of respiration, and loss of the normal elasticity of the lung.Examples of COPD are emphysema and chronic bronchitis. COPD is caused bychronic tobacco smoking (primary risk factor), occupational exposures,air pollution and genetic factors. Symptoms include: dyspnea onexertion, chronic cough and sputum production.

Neuromuscular Disease (NMD) is a broad term that encompasses manydiseases and ailments that impair the functioning of the muscles eitherdirectly via intrinsic muscle pathology, or indirectly via nervepathology. Some NMD patients are characterised by progressive muscularimpairment leading to loss of ambulation, being wheelchair-bound,swallowing difficulties, respiratory muscle weakness and, eventually,death from respiratory failure. Neuromuscular disorders can be dividedinto rapidly progressive and slowly progressive: (i) Rapidly progressivedisorders: Characterised by muscle impairment that worsens over monthsand results in death within a few years (e.g. Amyotrophic lateralsclerosis (ALS) and Duchenne muscular dystrophy (DMD) in teenagers);(ii) Variable or slowly progressive disorders: Characterised by muscleimpairment that worsens over years and only mildly reduces lifeexpectancy (e.g. Limb girdle, Facioscapulohumeral and Myotonic musculardystrophy). Symptoms of respiratory failure in NMD include: increasinggeneralised weakness, dysphagia, dyspnea on exertion and at rest,fatigue, sleepiness, morning headache, and difficulties withconcentration and mood changes.

Chest wall disorders are a group of thoracic deformities that result ininefficient coupling between the respiratory muscles and the thoraciccage. The disorders are usually characterised by a restrictive defectand share the potential of long term hypercapnic respiratory failure.Scoliosis and/or kyphoscoliosis may cause severe respiratory failure.Symptoms of respiratory failure include: dyspnea on exertion, peripheraloedema, orthopnea, repeated chest infections, morning headaches,fatigue, poor sleep quality and loss of appetite.

A range of therapies have been used to treat or ameliorate suchconditions. Furthermore, otherwise healthy individuals may takeadvantage of such therapies to prevent respiratory disorders fromarising. However, these have a number of shortcomings.

2.2.2 Therapy

Various therapies, such as Continuous Positive Airway Pressure (CPAP)therapy, Non-invasive ventilation (MV) and Invasive ventilation (IV)have been used to treat one or more of the above respiratory disorders.

Continuous Positive Airway Pressure (CPAP) therapy has been used totreat Obstructive Sleep Apnea (OSA). The mechanism of action is thatcontinuous positive airway pressure acts as a pneumatic splint and mayprevent upper airway occlusion, such as by pushing the soft palate andtongue forward and away from the posterior oropharyngeal wall. Treatmentof OSA by CPAP therapy may be voluntary, and hence patients may electnot to comply with therapy if they find devices used to provide suchtherapy one or more of: uncomfortable, difficult to use, expensive andaesthetically unappealing.

Non-invasive ventilation (NIV) provides ventilatory support to a patientthrough the upper airways to assist the patient breathing and/ormaintain adequate oxygen levels in the body by doing some or all of thework of breathing. The ventilatory support is provided via anon-invasive patient interface. NIV has been used to treat CSR andrespiratory failure, in forms such as OHS, COPD, NMD and Chest Walldisorders. In some forms, the comfort and effectiveness of thesetherapies may be improved.

Invasive ventilation (IV) provides ventilatory support to patients thatare no longer able to effectively breathe themselves and may be providedusing a tracheostomy tube. In some forms, the comfort and effectivenessof these therapies may be improved.

2.2.3 Treatment Systems

These therapies may be provided by a treatment system or device. Suchsystems and devices may also be used to diagnose a condition withouttreating it.

A treatment system may comprise a Respiratory Pressure Therapy Device(RPT device), an air circuit, a humidifier, a patient interface, anddata management.

2.2.3.1 Patient Interface

A patient interface may be used to interface respiratory equipment toits wearer, for example by providing a flow of air to an entrance to theairways. The flow of air may be provided via a mask to the nose and/ormouth, a tube to the mouth or a tracheostomy tube to the trachea of apatient. Depending upon the therapy to be applied, the patient interfacemay form a seal, e.g., with a region of the patient's face, tofacilitate the delivery of gas at a pressure at sufficient variance withambient pressure to effect therapy, e.g., at a positive pressure ofabout 10 cmH₂O relative to ambient pressure. For other forms of therapy,such as the delivery of oxygen, the patient interface may not include aseal sufficient to facilitate delivery to the airways of a supply of gasat a positive pressure of about 10 cmH₂O.

Certain other mask systems may be functionally unsuitable for thepresent field. For example, purely ornamental masks may be unable tomaintain a suitable pressure. Mask systems used for underwater swimmingor diving may be configured to guard against ingress of water from anexternal higher pressure, but not to maintain air internally at a higherpressure than ambient.

Certain masks may be clinically unfavourable for the present technologye.g. if they block airflow via the nose and only allow it via the mouth.

Certain masks may be uncomfortable or impractical for the presenttechnology if they require a patient to insert a portion of a maskstructure in their mouth to create and maintain a seal via their lips.

Certain masks may be impractical for use while sleeping, e.g. forsleeping while lying on one's side in bed with a head on a pillow.

The design of a patient interface presents a number of challenges. Theface has a complex three-dimensional shape. The size and shape of nosesand heads varies considerably between individuals. Since the headincludes bone, cartilage and soft tissue, different regions of the facerespond differently to mechanical forces. The jaw or mandible may moverelative to other bones of the skull. The whole head may move during thecourse of a period of respiratory therapy.

As a consequence of these challenges, some masks suffer from being oneor more of obtrusive, aesthetically undesirable, costly, poorly fitting,difficult to use, and uncomfortable especially when worn for longperiods of time or when a patient is unfamiliar with a system. Wronglysized masks can give rise to reduced compliance, reduced comfort andpoorer patient outcomes. Masks designed solely for aviators, masksdesigned as part of personal protection equipment (e.g. filter masks),SCUBA masks, or for the administration of anaesthetics may be tolerablefor their original application, but nevertheless such masks may beundesirably uncomfortable to be worn for extended periods of time, e.g.,several hours. This discomfort may lead to a reduction in patientcompliance with therapy. This is even more so if the mask is to be wornduring sleep.

CPAP therapy is highly effective to treat certain respiratory disorders,provided patients comply with therapy. If a mask is uncomfortable, ordifficult to use a patient may not comply with therapy. Since it isoften recommended that a patient regularly wash their mask, if a mask isdifficult to clean (e.g., difficult to assemble or disassemble),patients may not clean their mask and this may impact on patientcompliance.

While a mask for other applications (e.g. aviators) may not be suitablefor use in treating sleep disordered breathing, a mask designed for usein treating sleep disordered breathing may be suitable for otherapplications.

For these reasons, patient interfaces for delivery of CPAP during sleepform a distinct field.

2.2.3.1.1 Seal-Forming Structure

Patient interfaces may include a seal-forming structure. Since it is indirect contact with the patient's face, the shape and configuration ofthe seal-forming structure can have a direct impact the effectivenessand comfort of the patient interface.

A patient interface may be partly characterised according to the designintent of where the seal-forming structure is to engage with the face inuse. In one form of patient interface, a seal-forming structure maycomprise a first sub-portion to form a seal around the left naris and asecond sub-portion to form a seal around the right naris. In one form ofpatient interface, a seal-forming structure may comprise a singleelement that surrounds both nares in use. Such single element may bedesigned to for example overlay an upper lip region and a nasal bridgeregion of a face. In one form of patient interface a seal-formingstructure may comprise an element that surrounds a mouth region in use,e.g. by forming a seal on a lower lip region of a face. In one form ofpatient interface, a seal-forming structure may comprise a singleelement that surrounds both nares and a mouth region in use. Thesedifferent types of patient interfaces may be known by a variety of namesby their manufacturer including nasal masks, full-face masks, nasalpillows, nasal puffs and oro-nasal masks.

A seal-forming structure that may be effective in one region of apatient's face may be inappropriate in another region, e.g. because ofthe different shape, structure, variability and sensitivity regions ofthe patient's face. For example, a seal on swimming goggles thatoverlays a patient's forehead may not be appropriate to use on apatient's nose.

Certain seal-forming structures may be designed for mass manufacturesuch that one design fit and be comfortable and effective for a widerange of different face shapes and sizes. To the extent to which thereis a mismatch between the shape of the patient's face, and theseal-forming structure of the mass-manufactured patient interface, oneor both must adapt in order for a seal to form.

One type of seal-forming structure extends around the periphery of thepatient interface, and is intended to seal against the patient's facewhen force is applied to the patient interface with the seal-formingstructure in confronting engagement with the patient's face. Theseal-forming structure may include an air or fluid filled cushion, or amoulded or formed surface of a resilient seal element made of anelastomer such as a rubber. With this type of seal-forming structure, ifthe fit is not adequate, there will be gaps between the seal-formingstructure and the face, and additional force will be required to forcethe patient interface against the face in order to achieve a seal.

Another type of seal-forming structure incorporates a flap seal of thinmaterial positioned about the periphery of the mask so as to provide aself-sealing action against the face of the patient when positivepressure is applied within the mask. Like the previous style of a sealforming portion, if the match between the face and the mask is not good,additional force may be required to achieve a seal, or the mask mayleak. Furthermore, if the shape of the seal-forming structure does notmatch that of the patient, it may crease or buckle in use, giving riseto leaks.

Another type of seal-forming structure may comprise a friction-fitelement, e.g. for insertion into a naris, however some patients findthese uncomfortable.

Another form of seal-forming structure may use adhesive to achieve aseal. Some patients may find it inconvenient to constantly apply andremove an adhesive to their face.

A range of patient interface seal-forming structure technologies aredisclosed in the following patent applications, assigned to ResMedLimited: WO 1998/004310; WO 2006/074513; WO 2010/135785.

One form of nasal pillow is found in the Adam Circuit manufactured byPuritan Bennett. Another nasal pillow, or nasal puff is the subject ofU.S. Pat. No. 4,782,832 (Trimble et al.), assigned to Puritan-BennettCorporation.

ResMed Limited has manufactured the following products that incorporatenasal pillows: SWIFT™ nasal pillows mask, SWIFT™ II nasal pillows mask,SWIFT™ LT nasal pillows mask, SWIFT™ FX nasal pillows mask and MIRAGELIBERTY™ full-face mask. The following patent applications, assigned toResMed Limited, describe examples of nasal pillows masks: InternationalPatent Application WO2004/073778 (describing amongst other thingsaspects of the ResMed Limited SWIFT™ nasal pillows), US PatentApplication 2009/0044808 (describing amongst other things aspects of theResMed Limited SWIFT™ LT nasal pillows); International PatentApplications WO 2005/063328 and WO 2006/130903 (describing amongst otherthings aspects of the ResMed Limited MIRAGE LIBERTY™ full-face mask);International Patent Application WO 2009/052560 (describing amongstother things aspects of the ResMed Limited SWIFT™ FX nasal pillows).

2.2.3.1.2 Positioning and Stabilising

A seal-forming structure of a patient interface used for positive airpressure therapy is subject to the corresponding force of the airpressure to disrupt a seal. Thus a variety of techniques have been usedto position the seal-forming structure, and to maintain it in sealingrelation with the appropriate portion of the face.

One technique is the use of adhesives. See for example US PatentApplication Publication No. US 2010/0000534. However, the use ofadhesives may be uncomfortable for some.

Another technique is the use of one or more straps and/or stabilisingharnesses. Many such harnesses suffer from being one or more ofill-fitting, bulky, uncomfortable and awkward to use. When designed tobe worn on the patient's head such harnesses may be referred to asheadgear.

2.2.3.1.3 Pressurised Air Conduit

In one type of treatment system, a flow of pressurised air is providedto a patient interface through a conduit in an air circuit that fluidlyconnects to the patient interface so that, when the patient interface ispositioned on the patient's face during use, the conduit extends out ofthe patient interface forwards away from the patient's face. This maysometimes be referred to as an “elephant trunk” style of interface.

Some patients find such interfaces to be unsightly and are consequentlydeterred from wearing them, reducing patient compliance. Additionally,conduits connecting to an interface at the front of a patient's face maysometimes be vulnerable to becoming tangled up in bed clothes.

2.2.3.1.4 Pressurised Air Conduit Used for Positioning/Stabilising theSeal-Forming Structure

An alternative type of treatment system which seeks to address theseproblems comprises a patient interface in which a tube that deliverspressurised air to the patient's airways also functions as part of theheadgear to position and stabilise the seal-forming portion of thepatient interface to the appropriate part of the patient's face. Thistype of patient interface may be referred to as incorporating ‘headgeartubing’ or ‘conduit headgear’. Such patient interfaces allow the conduitin the air circuit providing the flow of pressurised air from arespiratory pressure therapy device to connect to the patient interfacein a position other than in front of the patient's face. One example ofsuch a treatment system is disclosed in US Patent Publication No. US2007/0246043, the contents of which are incorporated herein byreference, in which the conduit connects to a tube in the patientinterface through a port positioned in use on top of the patient's head.

The Philips DreamWear™ nasal mask includes such headgear tubing. Oneproblem with this mask is that the headgear tubes are silicone. Thesilicone conduit may cause discomfort to a patient when against the faceof a patient. Further, the weight of the headgear may cause somepatients to be uncomfortable during use.

Patient interfaces incorporating headgear tubing may provide someadvantages, for example avoiding a conduit connecting to the patientinterface at the front of a patient's face, which may be unsightly andobtrusive. However, it is desirable for patient interfaces incorporatingheadgear tubing to be comfortable for a patient to wear over a prolongedduration when the patient is asleep while forming an effective seal withthe patient's face.

2.2.3.2 Respiratory Pressure Therapy (RPT) Device

A respiratory pressure therapy (RPT) device may be used individually oras part of a system to deliver one or more of a number of therapiesdescribed above, such as by operating the device to generate a flow ofair for delivery to an interface to the airways. The flow of air may bepressure-controlled (for respiratory pressure therapies) orflow-controlled (for flow therapies such as HFT). Thus RPT devices mayalso act as flow therapy devices. Examples of RPT devices include a CPAPdevice and a ventilator.

Air pressure generators are known in a range of applications, e.g.industrial-scale ventilation systems. However, air pressure generatorsfor medical applications have particular requirements not fulfilled bymore generalised air pressure generators, such as the reliability, sizeand weight requirements of medical devices. In addition, even devicesdesigned for medical treatment may suffer from shortcomings, pertainingto one or more of: comfort, noise, ease of use, efficacy, size, weight,manufacturability, cost, and reliability.

An example of the special requirements of certain RPT devices isacoustic noise.

Table of noise output levels of prior RPT devices (one specimen only,measured using test method specified in ISO 3744 in CPAP mode at 10cmH₂O). A-weighted sound Year RPT Device name pressure level dB(A)(approx.) C-Series Tango ™ 31.9 2007 C-Series Tango ™ with Humidifier33.1 2007 S8 Escape ™ II 30.5 2005 S8 Escape ™ II with H4i ™ Humidifier31.1 2005 S9 AutoSet ™ 26.5 2010 S9 AutoSet ™ with H5i Humidifier 28.62010

One known RPT device used for treating sleep disordered breathing is theS9 Sleep Therapy System, manufactured by ResMed Limited. Another exampleof an RPT device is a ventilator. Ventilators such as the ResMedStellar™ Series of Adult and Paediatric Ventilators may provide supportfor invasive and non-invasive non-dependent ventilation for a range ofpatients for treating a number of conditions such as but not limited toNMD, OHS and COPD.

The ResMed Elisée™ 150 ventilator and ResMed VS III™ ventilator mayprovide support for invasive and non-invasive dependent ventilationsuitable for adult or paediatric patients for treating a number ofconditions. These ventilators provide volumetric and barometricventilation modes with a single or double limb circuit. RPT devicestypically comprise a pressure generator, such as a motor-driven bloweror a compressed gas reservoir, and are configured to supply a flow ofair to the airway of a patient. In some cases, the flow of air may besupplied to the airway of the patient at positive pressure. The outletof the RPT device is connected via an air circuit to a patient interfacesuch as those described above.

The designer of a device may be presented with an infinite number ofchoices to make. Design criteria often conflict, meaning that certaindesign choices are far from routine or inevitable. Furthermore, thecomfort and efficacy of certain aspects may be highly sensitive tosmall, subtle changes in one or more parameters.

2.2.3.3 Humidifier

Delivery of a flow of air without humidification may cause drying ofairways. The use of a humidifier with an RPT device and the patientinterface produces humidified gas that minimizes drying of the nasalmucosa and increases patient airway comfort. In addition in coolerclimates, warm air applied generally to the face area in and about thepatient interface is more comfortable than cold air. Humidifierstherefore often have the capacity to heat the flow of air was well ashumidifying it.

A range of artificial humidification devices and systems are known,however they may not fulfil the specialised requirements of a medicalhumidifier.

Medical humidifiers are used to increase humidity and/or temperature ofthe flow of air in relation to ambient air when required, typicallywhere the patient may be asleep or resting (e.g. at a hospital). Amedical humidifier for bedside placement may be small. A medicalhumidifier may be configured to only humidify and/or heat the flow ofair delivered to the patient without humidifying and/or heating thepatient's surroundings. Room-based systems (e.g. a sauna, an airconditioner, or an evaporative cooler), for example, may also humidifyair that is breathed in by the patient, however those systems would alsohumidify and/or heat the entire room, which may cause discomfort to theoccupants. Furthermore medical humidifiers may have more stringentsafety constraints than industrial humidifiers

While a number of medical humidifiers are known, they can suffer fromone or more shortcomings. Some medical humidifiers may provideinadequate humidification, some are difficult or inconvenient to use bypatients.

2.2.3.4 Data Management

There may be clinical reasons to obtain data to determine whether thepatient prescribed with respiratory therapy has been “compliant”, e.g.that the patient has used their RPT device according to one or more“compliance rules”. One example of a compliance rule for CPAP therapy isthat a patient, in order to be deemed compliant, is required to use theRPT device for at least four hours a night for at least 21 of 30consecutive days. In order to determine a patient's compliance, aprovider of the RPT device, such as a health care provider, may manuallyobtain data describing the patient's therapy using the RPT device,calculate the usage over a predetermined time period, and compare withthe compliance rule. Once the health care provider has determined thatthe patient has used their RPT device according to the compliance rule,the health care provider may notify a third party that the patient iscompliant.

There may be other aspects of a patient's therapy that would benefitfrom communication of therapy data to a third party or external system.

Existing processes to communicate and manage such data can be one ormore of costly, time-consuming, and error-prone.

2.2.3.5 Mandibular Repositioning

A mandibular repositioning device (MRD) or mandibular advancement device(MAD) is one of the treatment options for sleep apnea and snoring. It isan adjustable oral appliance available from a dentist or other supplierthat holds the lower jaw (mandible) in a forward position during sleep.The MRD is a removable device that a patient inserts into their mouthprior to going to sleep and removes following sleep. Thus, the MRD isnot designed to be worn all of the time. The MRD may be custom made orproduced in a standard form and includes a bite impression portiondesigned to allow fitting to a patient's teeth. This mechanicalprotrusion of the lower jaw expands the space behind the tongue, putstension on the pharyngeal walls to reduce collapse of the airway anddiminishes palate vibration.

In certain examples a mandibular advancement device may comprise anupper splint that is intended to engage with or fit over teeth on theupper jaw or maxilla and a lower splint that is intended to engage withor fit over teeth on the upper jaw or mandible. The upper and lowersplints are connected together laterally via a pair of connecting rods.The pair of connecting rods are fixed symmetrically on the upper splintand on the lower splint.

In such a design the length of the connecting rods is selected such thatwhen the MRD is placed in a patient's mouth the mandible is held in anadvanced position. The length of the connecting rods may be adjusted tochange the level of protrusion of the mandible. A dentist may determinea level of protrusion for the mandible that will determine the length ofthe connecting rods.

Some MRDs are structured to push the mandible forward relative to themaxilla while other MADs, such as the ResMed Narval CCTM MRD aredesigned to retain the mandible in a forward position. This device alsoreduces or minimises dental and temporo-mandibular joint (TMJ) sideeffects. Thus, it is configured to minimises or prevent any movement ofone or more of the teeth.

2.2.3.6 Vent Technologies

Some forms of treatment systems may include a vent to allow the washoutof exhaled carbon dioxide. The vent may allow a flow of gas from aninterior space of a patient interface, e.g., the plenum chamber, to anexterior of the patient interface, e.g., to ambient.

The vent may comprise an orifice and gas may flow through the orifice inuse of the mask. Many such vents are noisy. Others may become blocked inuse and thus provide insufficient washout. Some vents may be disruptiveof the sleep of a bed partner 1100 of the patient 1000, e.g. throughnoise or focussed airflow.

ResMed Limited has developed a number of improved mask venttechnologies. See International Patent Application Publication No. WO1998/034,665; International Patent Application Publication No. WO2000/078,381; US Patent No. 6,581,594; US Patent Application PublicationNo. US 2009/0050156; US Patent Application Publication No. 2009/0044808.

Table of noise of prior masks (ISO 17510-2: 2007, 10 cmH₂O pressure at 1m) A-weighted A-weighted sound power sound pressure level dB(A) dB(A)Year Mask name Mask type (uncertainty) (uncertainty) (approx.) Glue-on(*) nasal 50.9 42.9 1981 ResCare nasal 31.5 23.5 1993 standard (*)ResMed nasal 29.5 21.5 1998 Mirage ™ (*) ResMed nasal 36 (3) 28 (3) 2000UltraMirage ™ ResMed nasal 32 (3) 24 (3) 2002 Mirage Activa ™ ResMednasal 30 (3) 22 (3) 2008 Mirage Micro ™ ResMed nasal 29 (3) 22 (3) 2008Mirage ™ SoftGel ResMed nasal 26 (3) 18 (3) 2010 Mirage ™ FX ResMednasal pillows 37   29   2004 Mirage Swift ™ (*) ResMed nasal pillows 28(3) 20 (3) 2005 Mirage Swift ™ II ResMed nasal pillows 25 (3) 17 (3)2008 Mirage Swift ™ LT ResMed nasal pillows 21 (3) 13 (3) 2014 AirFitP10 (*) one specimen only, measured using test method specified in ISO3744 in CPAP mode at 10 cmH₂O)

Sound pressure values of a variety of objects are listed below

A-weighted sound Object pressure dB(A) Notes Vacuum cleaner: NilfiskWalter 68 ISO 3744 at 1 m Broadly Litter Hog: B+ Grade distanceConversational speech 60 1 m distance Average home 50 Quiet library 40Quiet bedroom at night 30 Background in TV studio 20

2.2.4 Screening, Diagnosis, and Monitoring Systems

Polysomnography (PSG) is a conventional system for diagnosis andmonitoring of cardio-pulmonary disorders, and typically involves expertclinical staff to apply the system. PSG typically involves the placementof 15 to 20 contact sensors on a patient in order to record variousbodily signals such as electroencephalography (EEG), electrocardiography(ECG), electrooculograpy (EOG), electromyography (EMG), etc. PSG forsleep disordered breathing has involved two nights of observation of apatient in a clinic, one night of pure diagnosis and a second night oftitration of treatment parameters by a clinician. PSG is thereforeexpensive and inconvenient. In particular it is unsuitable for homescreening/diagnosis/monitoring of sleep disordered breathing.

Screening and diagnosis generally describe the identification of acondition from its signs and symptoms. Screening typically gives atrue/false result indicating whether or not a patient's SDB is severeenough to warrant further investigation, while diagnosis may result inclinically actionable information. Screening and diagnosis tend to beone-off processes, whereas monitoring the progress of a condition cancontinue indefinitely. Some screening/diagnosis systems are suitableonly for screening/diagnosis, whereas some may also be used formonitoring.

Clinical experts may be able to screen, diagnose, or monitor patientsadequately based on visual observation of PSG signals. However, thereare circumstances where a clinical expert may not be available, or aclinical expert may not be affordable. Different clinical experts maydisagree on a patient's condition. In addition, a given clinical expertmay apply a different standard at different times.

3 BRIEF SUMMARY OF THE TECHNOLOGY

The present technology is directed towards providing medical devicesused in the screening, diagnosis, monitoring, amelioration, treatment,or prevention of respiratory disorders having one or more of improvedcomfort, cost, efficacy, ease of use and manufacturability.

A first aspect of the present technology relates to apparatus used inthe screening, diagnosis, monitoring, amelioration, treatment orprevention of a respiratory disorder.

Another aspect of the present technology relates to methods used in thescreening, diagnosis, monitoring, amelioration, treatment or preventionof a respiratory disorder.

An aspect of certain forms of the present technology is to providemethods and/or apparatus that improve the compliance of patients withrespiratory therapy.

One form of the present technology comprises a patient interface fordelivery of a supply of pressurised breathable gas to an entrance of apatient's airways.

An aspect of the present technology is directed to a patient interfacecomprising: a plenum chamber pressurisable to a therapeutic pressure ofat least 6 cmH2O above ambient air pressure, a seal-forming structureconstructed and arranged to form a seal with a region of the patient'sface surrounding an entrance to the patient's airways, a positioning andstabilising structure to provide a force to hold the seal-formingstructure in a therapeutically effective position on a head of apatient, the positioning and stabilising structure comprising: at leastone gas delivery tube to deliver the flow of air to the entrance of thepatient's airways via the seal-forming structure, and wherein the atleast one gas delivery tube includes: an elongate, tubular textileportion having an interior surface; and an impermeable layer joined tothe interior surface of the elongate, tubular textile portion; and atleast one connector formed at an end of the at least one gas deliverytube, the connector and the impermeable layer being formed from a singlepiece of homogeneous material.

An aspect of the present technology is directed to a patient interfacecomprising: a plenum chamber pressurisable to a therapeutic pressure ofat least 6 cmH2O above ambient air pressure, said plenum chamberincluding a plenum chamber inlet port sized and structured to receive aflow of air at the therapeutic pressure for breathing by a patient, aseal-forming structure constructed and arranged to form a seal with aregion of the patient's face surrounding an entrance to the patient'sairways, said seal-forming structure having a hole therein such that theflow of air at said therapeutic pressure is delivered to at least anentrance to the patient's nares, the seal-forming structure constructedand arranged to maintain said therapeutic pressure in the plenum chamberthroughout the patient's respiratory cycle in use; a positioning andstabilising structure to provide a force to hold the seal-formingstructure in a therapeutically effective position on a head of apatient, the positioning and stabilising structure comprising: at leastone gas delivery tube to deliver the flow of air to the entrance of thepatient's airways via the seal-forming structure, the at least one gasdelivery tube being constructed and arranged to contact, in use, atleast a region of the patient's head superior to an otobasion superiorof the patient's head, the at least one gas delivery tube having anexterior surface; and wherein the at least one gas delivery tubeincludes: an elongate, tubular textile portion having an interiorsurface; and an impermeable layer joined to the interior surface of theelongate, tubular textile portion; and at least one connector formed atan end of the at least one gas delivery tube, the connector and theimpermeable layer being formed from a single piece of homogeneousmaterial.

In examples of the preceding aspects, (a) one or more connectors may beformed around the perimeter of the at least one gas delivery tube, (b)the connectors may be positioned in opposition to one another relativeto a longitudinal axis of the at least one gas delivery tube, (c) theconnector may include a snap feature configured to provide tactileand/or audible feedback for a connection of the connector to anotherstructure, (d) the snap feature may be cantilevered from the end of theat least one gas delivery tube such that the connector flexes uponcontact with another component to facilitate the connection, (e) aconnector insert may be joined to the connector, (f) the snap featuremay be formed upon the connector insert, (g) the connector insert mayinclude one or more tabs projecting therefrom to engage portions of thematerial of the connector to form corresponding notches that receive andform a mechanical connection with the tabs, (f) the tabs may be formedwith an undercut such that the material of the connector is spread intothe undercut during molding to facilitate the mechanical connection,and/or (g) one or more connectors may be formed at each end of the atleast one gas delivery tube.

An aspect of the present technology is directed to a patient interfacecomprising: a plenum chamber pressurisable to a therapeutic pressure ofat least 6 cmH2O above ambient air pressure, a seal-forming structureconstructed and arranged to form a seal with a region of the patient'sface surrounding an entrance to the patient's airways, a positioning andstabilising structure to provide a force to hold the seal-formingstructure in a therapeutically effective position on a head of apatient, the positioning and stabilising structure comprising: at leastone gas delivery tube to deliver the flow of air to the entrance of thepatient's airways via the seal-forming structure, and wherein the atleast one gas delivery tube includes: an elongate, tubular textileportion having an exterior surface and an interior surface; and animpermeable layer joined to the interior surface of the elongate,tubular textile portion; and wherein the impermeable layer isconstructed from a single, homogeneous piece of material such that theimpermeable layer is cirumferentially continuous.

An aspect of the present technology is directed to a patient interfacecomprising: a plenum chamber pressurisable to a therapeutic pressure ofat least 6 cmH2O above ambient air pressure, said plenum chamberincluding a plenum chamber inlet port sized and structured to receive aflow of air at the therapeutic pressure for breathing by a patient, aseal-forming structure constructed and arranged to form a seal with aregion of the patient's face surrounding an entrance to the patient'sairways, said seal-forming structure having a hole therein such that theflow of air at said therapeutic pressure is delivered to at least anentrance to the patient's nares, the seal-forming structure constructedand arranged to maintain said therapeutic pressure in the plenum chamberthroughout the patient's respiratory cycle in use; a positioning andstabilising structure to provide a force to hold the seal-formingstructure in a therapeutically effective position on a head of apatient, the positioning and stabilising structure comprising: at leastone gas delivery tube to deliver the flow of air to the entrance of thepatient's airways via the seal-forming structure, the at least one gasdelivery tube being constructed and arranged to contact, in use, atleast a region of the patient's head superior to an otobasion superiorof the patient's head; and wherein the at least one gas delivery tubeincludes: an elongate, tubular textile portion having an exteriorsurface and an interior surface; and an impermeable layer joined to theinterior surface of the elongate, tubular textile portion; and whereinthe impermeable layer is constructed from a single, homogeneous piece ofmaterial such that the impermeable layer is cirumferentially continuous.

In examples of the preceding aspects, (a) the elongate, tubular textileportion may be constructed from an outer textile portion and an innertextile portion that are connected by joints, (b) the elongate, tubulartextile portion may be constructed from a single, continuous piece oftextile, (c) the elongate, tubular textile portion may be formed byweaving, (d) the elongate, tubular textile portion may be formed byknitting, (e) the elongate, tubular textile portion is constructed froma non-woven fabric, (f) the impermeable layer may be joined to theinterior surface of the elongate, tubular textile portion with amechanical connection, (g) the impermeable layer may be joined to theinterior surface of the elongate, tubular textile portion with achemical bond, (h) the elongate, tubular textile portion may comprisesynthetic fibers, (i) the synthetic fibers may be nylon, (j) thesynthetic fibers may be polyester, (k) the impermeable layer may beformed from a polymer, (1) the polymer may be one of: Liquid SiliconeRubber (LSR), Low Density Polyethylene (LDPE), High Density Polyethylene(HDPE), Polyethylene Terephtalate (PET), Polypropylene (PP), andPolyvinyl Chloride (PVC), (m) the exterior surface may have a curved,non-patient contacting side and a substantially flat patient contactingside, (n) the elongate, tubular textile portion may have an oval-shapedcross-section, (o) the elongate, tubular textile portion may have acircular cross-section, (p) the at least one gas delivery tube may beconstructed without any seams extending from the exterior surface, (q)the inner textile portion may have a substantially planarcross-sectional shape, wherein the outer textile portion has apre-determined non-planar cross-sectional shape, and the outer textileportion may be resilient such that when subjected to external force thecross-sectional shape of the outer textile portion is altered, and whenthe external force is released the outer textile portion returns to thepre-determined non-planar cross-sectional shape, (r) the inner textileportion may have different material properties than the outer textileportion, (s) the thickness of the impermeable layer may be substantiallyconsistent, (t) the thickness of the impermeable layer may vary in adirection parallel to the elongate, tubular textile portion'slongitudinal axis, (u) the thickness of the impermeable layer may varyradially, (v) the inner textile portion may be secured to the outertextile portion such that the outer textile portion imparts tension ontothe inner textile portion, (w) the at least one gas delivery tube may beconfigured to extend, in use, continuously from a right side of thepatient's head, along the parietal bone, to a left side of the patient'shead, (x) two gas delivery tubes, may each be configured to bepositioned against a corresponding lateral side of the patient's head inuse, (y) the inner textile portion may be joined to the outer textileportion at the joint such that a width of the joint is varied along alength of the at least one gas delivery tube, (z) the interior surfaceof the outer textile layer may have a positive curvature, (aa) the innertextile portion may have a zero curvature, (bb) the inner textileportion and the outer textile portion may be joined together withoutstitching, (cc) the at least one gas delivery tube may be constructedand arranged such that, during use, pressurized air expands the innertextile layer away from the outer textile layer, (dd) the outer textilelayer may be constructed from a conformable material, and theconformable material may be thermoformed to the non-planarcross-sectional shape, and/or (ee) the at least one gas delivery tubemay be thermoformed in a predetermined shape such that a first armextends along a first plane, and an upper portion extends along a secondplane that is substantially orthogonal to the first plane withoutexternal force or pressure.

Another aspect of the present technology relates to at least one gasdelivery tube having an inner textile layer and an outer textile layer,wherein the inner textile layer and the outer textile layer havedifferent cross-sectional shapes.

Another aspect of the present technology relates to at least one gasdelivery tube that includes an inner textile layer and an outer textilelayer. The inner textile layer has a substantially planarcross-sectional shape and the outer textile layer has a pre-determinednon-planar cross-sectional shape. The outer textile layer is resilientsuch that when subjected to external force the cross-sectional shape ofthe outer textile layer is altered, and when the external force isreleased the outer layer returns to the pre-determined non-planarcross-sectional shape.

Another aspect of the present technology relates to a gas delivery tubehaving an inner textile layer and an outer textile layer, wherein theouter textile layer is thermoformed to have a predetermined shape andthe inner textile layer is not thermoformed.

Another aspect of the present technology relates to at least one gasdelivery tube having an inner textile layer and an outer textile layer.The inner textile layer and the outer textile layer are joined along afirst longitudinal edge at a first joint and along a second longitudinaledge at a second joint, wherein between the first joint and the secondjoint the outer textile layer is spaced from the inner textile layer,wherein the outer textile layer is thermoformed to have a predeterminedshape and the inner textile layer is not thermoformed, and wherein theouter textile layer supports its own weight between the first joint andthe second joint such that the outer textile layer remains spaced fromthe inner textile layer when not supported by pressurized air.

Another aspect of the present technology relates to at least one gasdelivery tube having an inner textile layer and an outer textile layer,wherein the outer textile layer is more rigid than the inner textilelayer, wherein the inner textile layer and the outer textile layer arejoined along a first longitudinal edge and a second longitudinal edge,and wherein an air passageway is formed between the inner textile layerand the outer textile layer.

Another aspect of one form of the present technology comprises a patientinterface. The patient interface may include a plenum chamberpressurisable to a therapeutic pressure of at least 6 cmH2O aboveambient air pressure. The plenum chamber may include a plenum chamberinlet port sized and structured to receive a flow of air at thetherapeutic pressure for breathing by a patient. The patient interfacemay include a seal-forming structure constructed and arranged to form aseal with a region of the patient's face surrounding an entrance to thepatient's airways. The seal-forming structure may have a hole thereinsuch that the flow of air at said therapeutic pressure is delivered toat least an entrance to the patient's nares. The seal-forming structuremay be constructed and arranged to maintain said therapeutic pressure inthe plenum chamber throughout the patient's respiratory cycle in use.The patient interface may include at least one gas delivery tube todeliver the flow of air to the entrance of the patient's airways via theseal-forming structure, the at least one gas delivery tube beingconstructed and arranged to contact, in use, at least a region of thepatient's head superior to an otobasion superior of the patient's head.The at least one gas delivery tube may include an inner textile layerand an outer textile layer. The outer textile layer may have apre-determined non-planar cross-sectional shape. The outer textile layermay be resilient such that when subjected to external force thecross-sectional shape of the outer textile layer is altered, and whenthe external force is released the outer layer returns to thepre-determined non-planar cross-sectional shape.

In examples, (a) the inner textile layer may have different materialproperties than the outer textile layer, (b) the inner textile layer maycomprise an interior textile membrane, wherein during use whenpressurized with air, the interior textile membrane is configured topermit air transfer through the interior textile membrane, (c) the innertextile layer may comprise a conformable inner textile membrane, and theouter textile layer may comprise a conformable outer textile membrane,wherein the outer textile layer is thicker than the inner textile layer,(d) the inner textile layer may have a substantially planarcross-section, (e) the inner textile layer may be floppy, (f) the innertextile layer may be secured to the outer textile layer, wherein theouter textile layer imparts tension onto the inner textile layer, (g)the inner textile layer may comprise an exterior textile sheet and aninterior textile membrane, wherein the interior textile membrane isconfigured to resist the transfer of air through the exterior textilesheet, (h) the at least one gas delivery tube may be configured toextend continuously from a right side of the patient, along the parietalbone, to a left side of the patient, (i) the at least one gas deliverytube may include an air supply conduit, wherein when the patientinterface is worn by the patient the air supply conduit is locatedadjacent the parietal bone, (j) the outer textile layer may comprise anexterior textile sheet and an interior textile membrane, wherein aconformable sheet is sandwiched between the exterior textile sheet andthe interior textile membrane, (k) the inner textile layer may be joinedto the outer textile layer at a joint, wherein a width of the joint isvaried along a length of the at least one gas delivery tube, (l) theouter textile layer has an interior surface, wherein the interiorsurface of the outer textile layer may have a positive curvature, (m)the inner textile layer may have a zero curvature, (n) the inner textilelayer and the outer textile layer may be joined together withoutstitching, (o) the inner textile layer may comprise an inner interiortextile membrane, wherein the outer textile layer may include an outerinterior textile membrane, wherein the outer interior textile membraneof the outer textile layer and the inner interior textile membrane ofthe inner textile layer are joined together along edges of the at leastone gas delivery tube, wherein the inner interior textile membrane andthe outer interior textile membrane join the inner textile layer to theouter textile layer and form an air impermeable membrane between theinner textile layer and the outer textile layer, (p) the inner textilelayer and the outer textile layer are may be joined at a first edge by afirst joint and at a second edge by a second joint, and spaced from eachother between the first joint and the second joint, wherein rigidizersare not utilized along the inner textile layer between the first jointand the second joint, (q) during use and pressurized by air the innertextile layer may expand away from the outer textile layer, (r) theouter textile layer may include a conformable material, wherein theconformable material is thermoformed to the non-planar cross-sectionalshape, (s) the at least one gas delivery tube may be thermoformed in apredetermined shape such that a first arm extends along a first plane,and an upper portion extends along a second plane that is substantiallyorthogonal to the first plane without external force or pressure.

Another aspect of one form of the present technology comprises a patientinterface. The patient interface may include a plenum chamberpressurisable to a therapeutic pressure of at least 6 cmH2O aboveambient air pressure. The plenum chamber may include a plenum chamberinlet port sized and structured to receive a flow of air at thetherapeutic pressure for breathing by a patient. The patient interfacemay include a seal-forming structure constructed and arranged to form aseal with a region of the patient's face surrounding an entrance to thepatient's airways. The seal-forming structure may have a hole thereinsuch that the flow of air at said therapeutic pressure is delivered toat least an entrance to the patient's nares. The seal-forming structuremay be constructed and arranged to maintain said therapeutic pressure inthe plenum chamber throughout the patient's respiratory cycle in use.The patient interface may include at least one gas delivery tube todeliver the flow of air to the entrance of the patient's airways via theseal-forming structure, the at least one gas delivery tube beingconstructed and arranged to contact, in use, at least a region of thepatient's head superior to an otobasion superior of the patient's head.The at least one gas delivery tube may include an inner textile layerand an outer textile layer, wherein the inner textile layer and theouter textile layer may be joined along a first longitudinal edge at afirst joint and along a second longitudinal edge at a second joint.Between the first joint and the second joint the outer textile layer maybe spaced from the inner textile layer. The outer textile layer maysupport its own weight between the first joint and the second joint suchthat the outer textile layer remains spaced from the inner textile layerwhen not supported by pressurized air.

In examples according to the preceding paragraph, (a) the inner textilelayer may have different material properties than the outer textilelayer, (b) the inner textile layer may comprise an interior textilemembrane, wherein during use when pressurized with air, the interiortextile membrane is configured to permit air transfer through theinterior textile membrane, (c) the inner textile layer may comprise aconformable inner textile membrane, and the outer textile layer maycomprise a conformable outer textile membrane, wherein the outer textilelayer is thicker than the inner textile layer, (d) the inner textilelayer may have a substantially planar cross-section, (e) the innertextile layer may be floppy, (f) the inner textile layer may be securedto the outer textile layer, wherein the outer textile layer impartstension onto the inner textile layer, (g) the inner textile layer maycomprise an exterior textile sheet and an interior textile membrane,wherein the interior textile membrane is configured to resist thetransfer of air through the exterior textile sheet, (h) the at least onegas delivery tube may be configured to extend continuously from a rightside of the patient, along the parietal bone, to a left side of thepatient, (i) the at least one gas delivery tube may include an airsupply conduit, wherein when the patient interface is worn by thepatient the air supply conduit is located adjacent the parietal bone,(j) the outer textile layer may comprise an exterior textile sheet andan interior textile membrane, wherein a conformable sheet is sandwichedbetween the exterior textile sheet and the interior textile membrane,(k) the inner textile layer may be joined to the outer textile layer ata joint, wherein a width of the joint is varied along a length of the atleast one gas delivery tube, (l) the outer textile layer has an interiorsurface, wherein the interior surface of the outer textile layer has apositive curvature between the first joint and the second joint, (m) theinner textile layer may have a zero curvature between the first jointand the second joint, (n) the inner textile layer and the outer textilelayer may be joined together without stitching, (o) the inner textilelayer may comprise an inner interior textile membrane, wherein the outertextile layer may include an outer interior textile membrane, whereinthe outer interior textile membrane of the outer textile layer and theinner interior textile membrane of the inner textile layer are joinedtogether along edges of the at least one gas delivery tube, wherein theinner interior textile membrane and the outer interior textile membranejoin the inner textile layer to the outer textile layer and form an airimpermeable membrane between the inner textile layer and the outertextile layer, (p) the inner textile layer and the outer textile layerare may be joined at a first edge by a first joint and at a second edgeby a second joint, and spaced from each other between the first jointand the second joint, wherein rigidizers are not utilized along theinner textile layer between the first joint and the second joint, (q)during use and pressurized by air the inner textile layer may expandaway from the outer textile layer, (r) the outer textile layer mayinclude a conformable material, wherein the conformable material isthermoformed to the non-planar cross-sectional shape, (s) the at leastone gas delivery tube may be thermoformed in a predetermined shape suchthat a first arm extends along a first plane, and an upper portionextends along a second plane that is substantially orthogonal to thefirst plane without external force or pressure.

Another aspect of one form of the present technology comprises a patientinterface. The patient interface may include a plenum chamberpressurisable to a therapeutic pressure of at least 6 cmH2O aboveambient air pressure. The plenum chamber may include a plenum chamberinlet port sized and structured to receive a flow of air at thetherapeutic pressure for breathing by a patient. The patient interfacemay include a seal-forming structure constructed and arranged to form aseal with a region of the patient's face surrounding an entrance to thepatient's airways. The seal-forming structure may have a hole thereinsuch that the flow of air at said therapeutic pressure is delivered toat least an entrance to the patient's nares. The seal-forming structuremay be constructed and arranged to maintain said therapeutic pressure inthe plenum chamber throughout the patient's respiratory cycle in use.The patient interface may include at least one gas delivery tube todeliver the flow of air to the entrance of the patient's airways via theseal-forming structure, the at least one gas delivery tube beingconstructed and arranged to contact, in use, at least a region of thepatient's head superior to an otobasion superior of the patient's head.The at least one gas delivery tube may include an inner textile layerand an outer textile layer, wherein the outer textile layer is morerigid than the inner textile layer. The inner textile layer and theouter textile layer may be joined along a first longitudinal edge and asecond longitudinal edge. An air passageway may be formed between theinner textile layer and the outer textile layer.

In examples according to the preceding paragraph, (a) the outer textilelayer may have a pre-determined non-planar cross-sectional shape, andwherein the outer textile layer may be resilient such that whensubjected to external force the shape of the outer textile layer isaltered, and when the external force is released the outer layer returnsto the pre-determined non-planar cross-sectional shape, (b) between thefirst longitudinal edge and the second longitudinal edge the outertextile layer may be spaced from the inner textile layer; and whereinthe outer textile layer may support its own weight between the firstlongitudinal edge and the second longitudinal edge such that the outertextile layer remains spaced from the inner textile layer when notsupported by pressurized air, (c) the inner textile layer may comprisean interior textile membrane, wherein during use when pressurized withair, the interior textile membrane is configured to permit air transferthrough the interior textile membrane, (d) the inner textile layer maycomprise a conformable inner textile membrane, and the outer textilelayer may comprise a conformable outer textile membrane, wherein theouter textile layer may be thicker than the inner textile layer, (e) theinner textile layer may have a substantially planar cross-section, (f)the inner textile layer may be floppy, (g) the inner textile layer maybe secured to the outer textile layer, wherein the outer textile layermay impart tension onto the inner textile layer, (h) the inner textilelayer may comprise an exterior textile sheet and an interior textilemembrane, wherein the interior textile membrane may be configured toresist the transfer of air through the exterior textile sheet, (i) theat least one gas delivery tube may be configured to extend continuouslyfrom a right side of the patient, along the parietal bone, to a leftside of the patient, (j) the at least one gas delivery tube may includean air supply conduit, wherein when the patient interface is worn by thepatient the air supply conduit is located adjacent the parietal bone,(k) the outer textile layer may comprise an exterior textile sheet andan interior textile membrane, wherein a conformable sheet may besandwiched between the exterior textile sheet and the interior textilemembrane, (l) the inner textile layer may be joined to the outer textilelayer at a joint, wherein a width of the joint is varied along a lengthof the at least one gas delivery tube, (m) the outer textile layer hasan interior surface, wherein the interior surface of the outer textilelayer may have a positive curvature between the first longitudinal edgeand the second longitudinal edge, (n) the inner textile layer may have azero curvature between the first longitudinal edge and the secondlongitudinal edge, (o) the inner textile layer and the outer textilelayer may be joined together without stitching, (p) the inner textilelayer may comprise an inner interior textile membrane, wherein the outertextile layer may include an outer interior textile membrane, whereinthe outer interior textile membrane of the outer textile layer and theinner interior textile membrane of the inner textile layer may be joinedtogether along edges of the at least one gas delivery tube, wherein theinner interior textile membrane and the outer interior textile membranemay join the inner textile layer to the outer textile layer and form anair impermeable membrane between the inner textile layer and the outertextile layer, (q) the inner textile layer and the outer textile layerare joined at a first edge by a first joint and at a second edge by asecond joint, and spaced from each other between the first joint and thesecond joint, wherein rigidizers are not utilized along the innertextile layer between the first joint and the second joint, (r) duringuse and pressurized by air the inner textile layer may expand away fromthe outer textile layer, (s) the patient interface may be configured toallow the patient to breath from ambient through their mouth in theabsence of a flow of pressurised air through the plenum chamber inletport, or the patient interface is configured to leave the patient'smouth uncovered, (t) the plenum chamber may be constructed from atransparent material, (u) the patient interface may be configured sothat no part of the patient interface enters the mouth in use, (v) thepatient interface may be configured so that the seal-forming structuredoes not extend below a mental protuberance region in use, (w) thepatient interface may be constructed and arranged so that the plenumchamber does not cover the eyes in use, (x) the patient interface may beconfigured so that the positioning and stabilizing structure provides aretention force of at least (6 (g-f/cm2) x mask footprint area (cm2)) inuse, (y) the patient interface may be configured so that the positioningand stabilizing structure provides a force of less than (30 (g-f/cm2) xmask footprint area (cm2)) in use, (z) a portion of the positioning andstabilizing structure may be constructed to be breathable to allowmoisture vapour to escape and/or be transmitted therethrough.

Another aspect of the present technology is directed to a patientinterface that includes: a plenum chamber; a seal-forming structure; avent structure; and a positioning and stabilising structure to provide aforce to hold a seal-forming structure in a therapeutically effectiveposition on a patient's head. The positioning and stabilising structureincluding at least one gas delivery tube to receive the flow of air froma connection port and to deliver the flow of air to the entrance of thepatient's airways via the seal-forming structure, the gas delivery tubebeing constructed and arranged to contact, in use, at least a region ofthe patient's head superior to an otobasion superior of the patient'shead.

Another aspect of the present technology is directed to a positioningand stabilising structure comprising at least one gas delivery tube. Theat least one gas delivery tube may comprise a non-patient contactingportion comprising a first outer layer, and a first inner layercomprising air impermeable material. The at least one gas delivery tubemay comprise a patient contacting portion comprising a second outerlayer configured to lie against the patient's head in use on an opposingside of the gas delivery tube to the first outer layer, and a secondinner layer comprising air impermeable material.

Another aspect of the present technology is directed to a positioningand stabilising structure to provide a force to hold a seal-formingstructure in a therapeutically effective position on a patient's head,the seal-forming structure constructed and arranged to form a seal witha region of the patient's face surrounding an entrance to the patient'sairways for sealed delivery of a flow of air at a therapeutic pressureof at least 6 cmH2O above ambient air pressure throughout the patient'srespiratory cycle in use. The positioning and stabilising structure maycomprise at least one gas delivery tube to receive the flow of air froma connection port on top of the patient's head and to deliver the flowof air to the entrance of the patient's airways via the seal-formingstructure, the gas delivery tube being constructed and arranged tocontact, in use, at least a region of the patient's head superior to anotobasion superior of the patient's head, the gas delivery tubecomprising a tube wall defining a hollow interior through which air isable to flow to the seal-forming structure. The tube wall maycomprise 1) a non-patient contacting portion comprising a first outerlayer and a first inner layer comprising air impermeable material; and2) a patient contacting portion comprising a second outer layerconfigured to lie against the patient's head in use on an opposing sideof the gas delivery tube to the first outer layer and a second innerlayer comprising air impermeable material.

In examples: (a) the first outer layer comprises textile material; (b)the second outer layer comprises textile material; (c) the first innerlayer comprises thermoplastic material; (d) the second inner layercomprises thermoplastic material; (e) the non-patient contacting portioncomprises a first intermediate layer between the first outer layer andthe first inner layer; (f) the non-patient contacting portion comprisesa first adhesive layer bonding the first outer layer to the firstintermediate layer; (g) the non-patient contacting portion comprises asecond adhesive layer bonding the first intermediate layer to the firstinner layer; (h) the first intermediate layer comprises a foam material;(i) the first intermediate layer comprises a spacer fabric; (j) thefirst intermediate layer is thicker than the first outer layer; (k) thepatient contacting portion comprises a second intermediate layer betweenthe second outer layer and the second inner layer; (l) the patientcontacting portion comprises a first adhesive layer bonding the secondouter layer to the second intermediate layer; (m) the patient contactingportion comprises a second adhesive layer bonding the secondintermediate layer to the second inner layer; (n) the secondintermediate layer comprises a foam material; (o) the secondintermediate layer comprises a spacer fabric; and/or (p) the secondintermediate layer is thicker than the second outer layer.

In further examples: (a) the non-patient contacting portion comprises afirst adhesive layer bonding the first outer layer to the first innerlayer; (b) the patient contacting portion comprises a first adhesivelayer bonding the second outer layer to the second inner layer; (c) thepatient contacting portion and/or the non-patient contacting portion arethermoformed to shape; (d) the gas delivery tube comprises one of adome-shaped, trapezoidal or rectangular cross section; (e) the gasdelivery tube varies in width from 24 mm to 18 mm along a length of thegas delivery tube; (f) the gas delivery tube varies in height from 8 mmto 6 mm along a length of the gas delivery tube; and/or (g) the patientcontacting portion and the non-patient contacting portion are eachelongate and each comprise an anterior edge and a posterior edge, theanterior edges being joined along the length of the gas delivery tubeand the posterior edges being joined along the length of the gasdelivery tube.

In further examples: (a) the anterior edges are joined to form ananterior seam of the gas delivery tube and the posterior edges arejoined to form a posterior seam of the gas delivery tube; (b) theanterior seam and/or posterior seam are thermoformed; (c) the gasdelivery tube comprises an eyelet configured to connect to a backstrapof the positioning and stabilising structure; (d) the eyelet is formedby the patient-contacting portion and/or the non-patient contactingportion; and/or (e) the eyelet is formed by a seam connecting posterioredges of the patient contacting portion and the non-patient contactingportion.

According to another aspect of the present technology there is provideda positioning and stabilising structure to provide a force to hold aseal-forming structure in a therapeutically effective position on apatient's head, the seal-forming structure constructed and arranged toform a seal with a region of the patient's face surrounding an entranceto the patient's airways for sealed delivery of a flow of air at atherapeutic pressure of at least 6 cmH2O above ambient air pressurethroughout the patient's respiratory cycle in use. The positioning andstabilising structure may comprise at least one gas delivery tube toreceive the flow of air from on top of the patient's head and to deliverthe flow of air to the entrance of the patient's airways via theseal-forming structure, the gas delivery tube being constructed andarranged to contact, in use, at least a region of the patient's headsuperior to an otobasion superior of the patient's head, the gasdelivery tube comprising a tube wall defining a hollow interior throughwhich air is able to flow to the seal-forming structure. The tube wallmay comprise 1) an elongate patient contacting portion configured to lieagainst the patient's head in use; and 2) an elongate non-patientcontacting portion on an opposing side of the gas delivery tube to thepatient contacting portion, wherein the non-patient contacting portionis pulled by the patient contacting portion into a predetermined shapecreating the hollow interior of the gas delivery tube.

In examples: (a) the gas delivery tube is biased towards an openconfiguration (b) the non-patient contacting portion is biased towards aflat shape; (c) the non-patient contacting portion is biased byelasticity in one or more materials forming the non-patient contactingportion; (d) the predetermined shape is a non-flat shape; (e) the gasdelivery tube comprises a trapezoidal cross section; (f) the patientcontacting portion comprises a non-flat shape; (g) the patientcontacting portion comprises a flatter shape than the non-patientcontacting portion; (h) the patient contacting portion is under tensionacross a width of the patient contacting portion; (i) the non-patientcontacting portion is pulled by the patient contacting portion at edgesalong a length of the non-patient contacting portion; (j) thenon-patient contacting portion and the patient-contacting portion arejoined at a pair of seams; (k) the patient contacting portion and thenon-patient contacting portion each comprise an anterior edge and aposterior edge, the anterior edges being joined along the length of thegas delivery tube and the posterior edges being joined along the lengthof the gas delivery tube; (l) the anterior edges are joined to form ananterior seam of the gas delivery tube and the posterior edges arejoined to form a posterior seam of the gas delivery tube; (m) theanterior seam and/or posterior seam are thermoformed; (n) the patientcontacting portion and the non-patient contacting portion arethermoformed.

In examples: (a) the patient contacting portion and/or the non-patientcontacting portion comprise a plurality of layers; (b) the patientcontacting portion comprises a first outer later comprising a textile orfoam material; (c) the non-patient contacting portion comprises a secondouter layer comprising a textile or foam material; (d) the patientcontacting portion and/or the non-patient contacting portion comprisesan intermediate layer comprising a foam material or spacer fabricmaterial.

In further examples: (a) the patient contacting portion may be stifferthan the non-patient contacting portion; (b) the non-patient contactingportion may be more stretchable than the patient-contacting portion; (c)the patient contacting portion may comprise a greater thickness than thenon-patient contacting portion; (d) the patient contacting portion maycomprise a medially-facing surface configured to lie against thepatient's head having a higher coefficient of friction with respect tothe patient's skin than a laterally-facing surface of the non-patientcontacting portion.

In some examples, the positioning and stabilising structure comprises apair of gas delivery tubes.

According to one aspect of the present technology there is provided apositioning and stabilising structure to provide a force to hold aseal-forming structure in a therapeutically effective position on apatient's head, the seal-forming structure constructed and arranged toform a seal with a region of the patient's face surrounding an entranceto the patient's airways for sealed delivery of a flow of air at atherapeutic pressure of at least 6 cmH2O above ambient air pressurethroughout the patient's respiratory cycle in use. The positioning andstabilising structure may comprise at least one gas delivery tube toreceive the flow of air from a connection port on top of the patient'shead and to deliver the flow of air to the entrance of the patient'sairways via the seal-forming structure, the gas delivery tube beingconstructed and arranged to contact, in use, at least a region of thepatient's head superior to an otobasion superior of the patient's head,the gas delivery tube comprising a tube wall defining a hollow interiorthrough which air is able to flow to the seal-forming structure. Thetube wall may comprise 1) a patient contacting portion comprising afirst outer layer comprising a textile or foam material configured tolie against the patient's head in use; and 2) a non-patient contactingportion comprising a second outer layer comprising a textile or foammaterial on an opposing side of the gas delivery tube to the first outerlayer.

In examples: (a) the patient contacting portion comprises a greaterstiffness than the non-patient contacting portion; (b) the patientcontacting portion comprises a greater thickness than the non-patientcontacting portion; (c) the patient contacting portion is thermoformedby a first thermoforming process and the non-patient contacting portionis thermoformed by a second thermoforming process, wherein the firstthermoforming process provides a greater stiffness to the patientcontacting portion than the second thermoforming process provides to thenon-patient contacting portion; (d) the patient contacting portion andthe non-patient contacting portion are each formed by layers, thepatient contacting portion comprising a greater number of layers thanthe non- patient contacting portion; (e) the patient contacting portioncomprises a rigidising layer; (f) the patient contacting portioncomprises a rigidising member.

In further examples, (a) the patient contacting portion and/or thenon-patient contacting portion may comprise a plurality of layers; (b)the patient contacting portion may comprise a first thermoplastic innerlayer defining at least a portion of an air path within the gas deliverytube; (c) the patient contacting portion may comprise a firstintermediate layer between the first outer layer and the firstthermoplastic inner layer; (d) the patient contacting portion maycomprise a first adhesive layer bonding the first outer layer to thefirst intermediate layer; (e) the patient contacting portion maycomprise a second adhesive layer bonding the first intermediate layer tothe first thermoplastic inner layer; and/or (f) the first intermediatelayer may be formed from a foam material or a spacer fabric material.

In further examples: (a) the non-patient contacting portion may comprisea second thermoplastic inner layer defining at least a portion of theair path within the gas delivery tube; (b) the non-patient contactingportion may comprise a first adhesive layer bonding the second outerlayer to the second thermoplastic inner layer; (c) alternatively, thenon-patient contacting portion may comprise a second intermediate layerbetween the second outer layer and the second thermoplastic inner layer;(d) the patient contacting portion may comprise a first adhesive layerbonding the second outer layer to the second intermediate layer; (e) thepatient contacting portion may comprise a second adhesive layer bondingthe second intermediate layer to the second thermoplastic inner layer;and/or (f) the second intermediate layer may be formed from a foammaterial.

In further examples: (a) the patient contacting portion and/or thenon-patient contacting portion may be thermoformed to shape; (b) the gasdelivery tube may comprise a dome-shaped cross section; (c) the gasdelivery tube may vary in width from 34 mm to 18 mm along a length ofthe gas delivery tube; and/or (d) the gas delivery tube may vary inheight from 8 mm to 6 mm along a length of the gas delivery tube.

According to another aspect of the present technology there is provideda positioning and stabilising structure to provide a force to hold aseal-forming structure in a therapeutically effective position on apatient's head, the seal-forming structure constructed and arranged toform a seal with a region of the patient's face surrounding an entranceto the patient's airways for sealed delivery of a flow of air at atherapeutic pressure of at least 6 cmH2O above ambient air pressurethroughout the patient's respiratory cycle in use. The positioning andstabilising structure may comprise at least one gas delivery tube toreceive the flow of air from on top of the patient's head and to deliverthe flow of air to the entrance of the patient's airways via theseal-forming structure, the gas delivery tube being constructed andarranged to contact, in use, at least a region of the patient's headsuperior to an otobasion superior of the patient's head, the gasdelivery tube comprising a tube wall defining a hollow interior throughwhich air is able to flow to the seal-forming structure. The tube wallmay comprise 1) a patient contacting portion configured to lie againstthe patient's head in use; and 2) a non-patient contacting portion on anopposing side of the gas delivery tube to the patient contactingportion.

In examples: (a) the patient contacting portion and/or the non-patientcontacting portion may comprise a plurality of layers; (b) the patientcontacting portion may comprise a first outer later comprising a textileor foam material; (c) the non-patient contacting portion may comprise asecond outer layer comprising a textile or foam material; (d) thepatient contacting portion and/or the non-patient contacting portion maycomprise an intermediate layer comprising a foam material or spacerfabric material.

In further examples: (a) the gas delivery tube may comprise a domeshaped cross section; (b) the gas delivery tube may comprise arectangular cross section with two or more rounded corners; (c) thepatient contacting portion may be stiffer than the non-patientcontacting portion; (d) the non-patient contacting portion may be morestretchable than the patient-contacting portion; (e) the patientcontacting portion may comprise a greater thickness than the non-patientcontacting portion; (f) the patient contacting portion may comprise amedially-facing surface configured to lie against the patient's headhaving a higher coefficient of friction with respect to the patient'sskin than a laterally-facing surface of the non-patient contactingportion.

In further examples: (a) the gas delivery tube may be biased into anopen configuration; (b) the non-patient contacting portion may be biasedtowards a flat shape and the patient contacting portion may pull thenon-patient contacting portion into a curved shape to produce the hollowinterior of the gas delivery tube; (c) the patient contacting portionand the non-patient contacting portion may each be elongate and eachcomprising an anterior edge and a posterior edge, the anterior edgesbeing joined along the length of the gas delivery tube and the posterioredges being joined along the length of the gas delivery tube; (d) afterthe anterior edges and posterior edges are joined, the patientcontacting portion and/or the non-patient contacting portion may beunder tension; (e) the anterior edges may be joined to form an anteriorseam of the gas delivery tube and the posterior edges may be joined toform a posterior seam of the gas delivery tube; (f) the anterior seamand/or posterior seam may be thermoformed; (g) the anterior seam mayhave a different rigidity to the posterior seam; (h) the anterior seammay comprise a greater rigidity than the posterior seam; (i) theanterior seam and/or the posterior seam may have a rigidity which variesalong the length of the gas delivery tube; (j) the rigidity of theanterior seam and/or the posterior seam may be greater at an inferiorportion of the gas delivery tube than at a superior portion of the gasdelivery tube; (k) the gas delivery tube may comprise an eyeletconfigured to connect to a backstrap of the positioning and stabilisingstructure; (l) the eyelet may be formed by the patient-contactingportion and/or the non-patient contacting portion; (m) the eyelet may beformed by a seam connecting posterior edges of the patient contactingportion and the non-patient contacting portion.

According to one aspect of the present technology there is provided apositioning and stabilising structure to provide a force to hold aseal-forming structure in a therapeutically effective position on apatient's head, the seal-forming structure constructed and arranged toform a seal with a region of the patient's face surrounding an entranceto the patient's airways for sealed delivery of a flow of air at atherapeutic pressure of at least 6 cmH2O above ambient air pressurethroughout the patient's respiratory cycle in use. The positioning andstabilising structure may comprise at least one gas delivery tube toreceive the flow of air from a connection port on top of the patient'shead and to deliver the flow of air to the entrance of the patient'sairways via the seal-forming structure, the gas delivery tube beingconstructed and arranged to contact, in use, at least a region of thepatient's head superior to an otobasion superior of the patient's head,the gas delivery tube comprising a tube wall defining a hollow interiorthrough which air is able to flow to the seal-forming structure. Thetube wall may comprise 1) a patient contacting portion comprising afirst outer layer comprising a textile or foam material configured tolie against the patient's head in use; and 2) a non-patient contactingportion comprising a second outer layer comprising a textile or foammaterial on an opposing side of the gas delivery tube to the first outerlayer, wherein at least one seam is formed by an edge of the non-patientcontacting portion being joined to a respective edge of the patientcontacting portion.

In examples: (a) the at least one seam provides rigidity to the at leastone gas delivery tube; (b) the at least one seam is formed by athermoforming process; (c) the at least one seam comprises rigidityprovided by compression of the edges forming the seam during thethermoforming process; (d) the at least one seam is welded.

In examples: (a) the at least one gas delivery tube comprises a superiortube portion and an inferior tube portion; (b) the at least one seamcomprises a greater stiffness in the inferior tube portion of the gasdelivery tube than in the superior tube portion; (c) the greaterstiffness of the at least one seam in the inferior tube portion isprovided by a greater compression of the edges forming the seam in theinferior tube portion during a thermoforming process than of the edgesforming the seam in the superior tube portion; (d) the at least one seamcomprises a greater thickness in the inferior tube portion of the gasdelivery tube; (e) the at least one seam comprises a greater width inthe inferior tube portion of the gas delivery tube than in the superiortube portion.

In examples: (a) the at least one seam comprises an anterior seam,wherein the patient contacting portion and the non-patient contactingportion of the gas delivery tube each comprises an anterior edge, theanterior edges of the patient contacting portion and the non-patientcontacting portion being joined to form the anterior seam; (b) the atleast one seam comprises a posterior seam, wherein the patientcontacting portion and the non-patient contacting portion of the gasdelivery tube each comprises a posterior edge, the posterior edges ofthe patient contacting portion and the non-patient contacting portionbeing joined to form the posterior seam; (c) the at least one seamcomprises an anterior seam and a posterior seam, wherein the patientcontacting portion and the non-patient contacting portion of the gasdelivery tube each comprises an anterior edge and a posterior edge, therespective anterior edges being joined to form an anterior seam and therespective posterior edges being joined to form a posterior seam.

In examples: (a) the anterior seam comprises a greater stiffness thanthe posterior seam; (b) the greater stiffness of the anterior seam isprovided by a greater compression of the edges forming the anterior seamduring a thermoforming process than of the edges forming the posteriorseam; (c) the anterior seam comprises a greater thickness than theposterior seam; (d) the anterior seam comprises a greater width than theposterior seam.

In examples: (a) the at least one seam comprises a posterior seam,wherein the patient contacting portion and the non-patient contactingportion of the gas delivery tube each comprises a posterior edge, theposterior edges of the patient contacting portion and the non-patientcontacting portion being joined to form the posterior seam; (b) theposterior seam comprises a widened portion, the widened portionconfigured to connect with a strap of the positioning and stabilisingstructure; (c) the posterior seam comprises an eyelet configured toconnect with the strap; (d) the posterior seam comprises a holeconfigured to receive the strap, the hole allowing the strap to bepassed therethrough and looped back and secured onto itself; (e) theeyelet in the posterior seam comprises a slit; (f) the positioning andstabilising structure comprises an eyelet rigidising portion configuredto reinforce the eyelet; (g) the eyelet rigidising portion is providedwithin the hole in the posterior seam and is configured to reinforce theshape of the hole; (h) the eyelet rigidising portion is substantiallyrigid.

According to one aspect of the present technology, there is provided apatient interface. The patient interface may comprise 1) a plenumchamber pressurisable to a therapeutic pressure of at least 6 cmH2Oabove ambient air pressure, said plenum chamber including a plenumchamber inlet port sized and structured to receive a flow of air at thetherapeutic pressure for breathing by a patient; 2) a seal-formingstructure constructed and arranged to form a seal with a region of thepatient's face surrounding an entrance to the patient's airways, saidseal-forming structure having a hole therein such that the flow of airat said therapeutic pressure is delivered to at least an entrance to thepatient's nares, the seal-forming structure constructed and arranged tomaintain said therapeutic pressure in the plenum chamber throughout thepatient's respiratory cycle in use; 3) a positioning and stabilisingstructure according to any one of the above aspects; and 4) a ventstructure to allow a continuous flow of gases exhaled by the patientfrom an interior of the plenum chamber to ambient, said vent structurebeing sized and shaped to maintain the therapeutic pressure in theplenum chamber in use, wherein the patient interface is configured toallow the patient to breath from ambient through their mouth in theabsence of a flow of pressurised air through the plenum chamber inletport, or the patient interface is configured to leave the patient'smouth uncovered.

Another aspect of certain forms of the present technology is a systemfor treating a respiratory disorder comprising a patient interfaceaccording to any one or more of the other aspects of the presenttechnology, an air circuit and a source of air at positive pressure.

Another aspect of one form of the present technology is a patientinterface that is moulded or otherwise constructed with a perimetershape which is complementary to that of an intended wearer.

An aspect of one form of the present technology is a method ofmanufacturing the components of the medical device.

Another aspect of certain forms of the present technology is a patientinterface comprising a seal-forming structure configured to leave thepatient's mouth uncovered in use.

Another aspect of certain forms of the present technology is a patientinterface comprising a seal-forming structure configured so that no partof the seal-forming structure enters the mouth in use.

Another aspect of certain forms of the present technology is a patientinterface comprising a seal-forming structure configured so that theseal-forming structure does not extend internally of the patient'sairways.

Another aspect of certain forms of the present technology is a patientinterface comprising a seal-forming structure configured so that theseal-forming structure does not extend below a mental protuberanceregion in use.

Another aspect of certain forms of the present technology is a patientinterface constructed and arranged to leave a patient's eyes uncoveredin use.

Another aspect of certain forms of the present technology is a patientinterface constructed and arranged to allow a patient to breathe ambientair in the event of a power failure.

Another aspect of certain forms of the present technology is a patientinterface comprising a seal forming structure configured to form a sealon an underside of a patient's nose without contacting a nasal bridgeregion of the patient's nose.

Another aspect of certain forms of the present technology is a patientinterface comprising a vent and a plenum chamber, wherein the patientinterface is constructed and arranged so that gases from an interior ofthe plenum chamber may pass to ambient via the vent.

Another aspect of certain forms of the present technology is a patientinterface constructed and arranged so that a patient may lie comfortablyin a side or lateral sleeping position, in use of the patient interface.

Another aspect of certain forms of the present technology is a patientinterface constructed and arranged so that a patient may lie comfortablyin a supine sleeping position, in use of the patient interface.

Another aspect of certain forms of the present technology is a patientinterface constructed and arranged so that a patient may lie comfortablyin a prone sleeping position, in use of the patient interface.

An aspect of certain forms of the present technology is a medical devicethat is easy to use, e.g. by a person who does not have medicaltraining, by a person who has limited dexterity, vision or by a personwith limited experience in using this type of medical device.

An aspect of one form of the present technology is a portable RPT devicethat may be carried by a person, e.g., around the home of the person.

An aspect of one form of the present technology is a patient interfacethat may be washed in a home of a patient, e.g., in soapy water, withoutrequiring specialised cleaning equipment.

Of course, portions of the aspects may form sub-aspects of the presenttechnology. Also, various ones of the sub-aspects and/or aspects may becombined in various manners and also constitute additional aspects orsub-aspects of the present technology.

Other features of the technology will be apparent from consideration ofthe information contained in the following detailed description,abstract, drawings and claims.

BRIEF DESCRIPTION OF THE DRAWINGS

The present technology is illustrated by way of example, and not by wayof limitation, in the figures of the accompanying drawings, in whichlike reference numerals refer to similar elements including:

4.1 Treatment Systems

FIG. 1A shows a system including a patient 1000 wearing a patientinterface 3000, in the form of nasal pillows, receiving a supply of airat positive pressure from an RPT device 4000. Air from the RPT device4000 is humidified in a humidifier 5000, and passes along an air circuit4170 to the patient 1000. A bed partner 1100 is also shown. The patientis sleeping in a supine sleeping position.

FIG. 1B shows a system including a patient 1000 wearing a patientinterface 3000, in the form of a nasal mask, receiving a supply of airat positive pressure from an RPT device 4000. Air from the RPT device ishumidified in a humidifier 5000, and passes along an air circuit 4170 tothe patient 1000.

FIG. 1C shows a system including a patient 1000 wearing a patientinterface 3000, in the form of a full-face mask, receiving a supply ofair at positive pressure from an RPT device 4000. Air from the RPTdevice is humidified in a humidifier 5000, and passes along an aircircuit 4170 to the patient 1000. The patient is sleeping in a sidesleeping position.

4.2 Respiratory System and Facial Anatomy

FIG. 2A shows an overview of a human respiratory system including thenasal and oral cavities, the larynx, vocal folds, oesophagus, trachea,bronchus, lung, alveolar sacs, heart and diaphragm.

FIG. 2B shows a view of a human upper airway including the nasal cavity,nasal bone, lateral nasal cartilage, greater alar cartilage, nostril,lip superior, lip inferior, larynx, hard palate, soft palate,oropharynx, tongue, epiglottis, vocal folds, oesophagus and trachea.

FIG. 2C is a front view of a face with several features of surfaceanatomy identified including the lip superior, upper vermilion, lowervermilion, lip inferior, mouth width, endocanthion, a nasal ala,nasolabial sulcus and cheilion. Also indicated are the directionssuperior, inferior, radially inward and radially outward.

FIG. 2D is a side view of a head with several features of surfaceanatomy identified including glabella, sellion, pronasale, subnasale,lip superior, lip inferior, supramenton, nasal ridge, alar crest point,otobasion superior and otobasion inferior. Also indicated are thedirections superior & inferior, and anterior & posterior.

FIG. 2E is a further side view of a head. The approximate locations ofthe Frankfort horizontal and nasolabial angle are indicated. The coronalplane is also indicated.

FIG. 2F shows a base view of a nose with several features identifiedincluding naso-labial sulcus, lip inferior, upper Vermilion, naris,subnasale, columella, pronasale, the major axis of a naris and themidsagittal plane.

FIG. 2G shows a side view of the superficial features of a nose.

FIG. 2H shows subcutaneal structures of the nose, including lateralcartilage, septum cartilage, greater alar cartilage, lesser alarcartilage, sesamoid cartilage, nasal bone, epidermis, adipose tissue,frontal process of the maxilla and fibrofatty tissue.

FIG. 2I shows a medial dissection of a nose, approximately severalmillimeters from the midsagittal plane, amongst other things showing theseptum cartilage and medial crus of greater alar cartilage.

FIG. 2J shows a front view of the bones of a skull including thefrontal, nasal and zygomatic bones. Nasal concha are indicated, as arethe maxilla, and mandible.

FIG. 2K shows a lateral view of a skull with the outline of the surfaceof a head, as well as several muscles. The following bones are shown:frontal, sphenoid, nasal, zygomatic, maxilla, mandible, parietal,temporal and occipital. The mental protuberance is indicated. Thefollowing muscles are shown: digastricus, masseter, sternocleidomastoidand trapezius.

FIG. 2L shows an anterolateral view of a nose.

4.3 Patient Interface

FIG. 3A shows a patient interface in the form of a nasal mask inaccordance with one form of the present technology.

FIG. 3B shows a schematic of a cross-section through a structure at apoint. An outward normal at the point is indicated. The curvature at thepoint has a positive sign, and a relatively large magnitude whencompared to the magnitude of the curvature shown in FIG. 3C.

FIG. 3C shows a schematic of a cross-section through a structure at apoint. An outward normal at the point is indicated. The curvature at thepoint has a positive sign, and a relatively small magnitude whencompared to the magnitude of the curvature shown in FIG. 3B.

FIG. 3D shows a schematic of a cross-section through a structure at apoint. An outward normal at the point is indicated. The curvature at thepoint has a value of zero.

FIG. 3E shows a schematic of a cross-section through a structure at apoint. An outward normal at the point is indicated. The curvature at thepoint has a negative sign, and a relatively small magnitude whencompared to the magnitude of the curvature shown in FIG. 3F.

FIG. 3F shows a schematic of a cross-section through a structure at apoint. An outward normal at the point is indicated. The curvature at thepoint has a negative sign, and a relatively large magnitude whencompared to the magnitude of the curvature shown in FIG. 3E.

FIG. 3G shows a cushion for a mask that includes two pillows. Anexterior surface of the cushion is indicated. An edge of the surface isindicated. Dome and saddle regions are indicated.

FIG. 3H shows a cushion for a mask. An exterior surface of the cushionis indicated. An edge of the surface is indicated. A path on the surfacebetween points A and B is indicated. A straight line distance between Aand B is indicated. Two saddle regions and a dome region are indicated.

FIG. 3I shows the surface of a structure, with a one dimensional hole inthe surface. The illustrated plane curve forms the boundary of a onedimensional hole.

FIG. 3J shows a cross-section through the structure of Fig.31. Theillustrated surface bounds a two dimensional hole in the structure ofFIG. 31.

FIG. 3K shows a perspective view of the structure of FIG. 31, includingthe two dimensional hole and the one dimensional hole. Also shown is thesurface that bounds a two dimensional hole in the structure of FIG. 31.

FIG. 3L shows a mask having an inflatable bladder as a cushion.

FIG. 3M shows a cross-section through the mask of FIG. 3L, and shows theinterior surface of the bladder. The interior surface bounds the twodimensional hole in the mask.

FIG. 3N shows a further cross-section through the mask of FIG. 3L. Theinterior surface is also indicated.

FIG. 3O illustrates a left-hand rule.

FIG. 3P illustrates a right-hand rule.

FIG. 3Q shows a left ear, including the left ear helix.

FIG. 3R shows a right ear, including the right ear helix.

FIG. 3S shows a right-hand helix.

FIG. 3T shows a view of a mask, including the sign of the torsion of thespace curve defined by the edge of the sealing membrane in differentregions of the mask.

FIG. 3U shows a view of a plenum chamber 3200 showing a sagittal planeand a mid-contact plane.

FIG. 3V shows a view of a posterior of the plenum chamber of FIG. 3U.The direction of the view is normal to the mid-contact plane. Thesagittal plane in FIG. 3V bisects the plenum chamber into left-hand andright-hand sides.

FIG. 3W shows a cross-section through the plenum chamber of FIG. 3V, thecross-section being taken at the sagittal plane shown in FIG. 3V. A‘mid-contact’ plane is shown. The mid-contact plane is perpendicular tothe sagittal plane. The orientation of the mid-contact plane correspondsto the orientation of a chord 3210 which lies on the sagittal plane andjust touches the cushion of the plenum chamber at two points on thesagittal plane: a superior point 3220 and an inferior point 3230.Depending on the geometry of the cushion in this region, the mid-contactplane may be a tangent at both the superior and inferior points.

FIG. 3X shows the plenum chamber 3200 of FIG. 3U in position for use ona face. The sagittal plane of the plenum chamber 3200 generallycoincides with the midsagittal plane of the face when the plenum chamberis in position for use. The mid-contact plane corresponds generally tothe ‘plane of the face’ when the plenum chamber is in position for use.In FIG. 3X the plenum chamber 3200 is that of a nasal mask, and thesuperior point 3220 sits approximately on the sellion, while theinferior point 3230 sits on the lip superior.

FIG. 4A shows an isometric view of a patient interface in accordancewith an example of the present technology.

FIG. 4B shows an isometric view of the patient interface worn on apatient.

FIG. 4C shows a side view of the patient interface worn on a patient in.

FIG. 4D shows a top view of the patient interface worn on a patient.

FIG. 4E shows an isometric view of a tube of the patient interface in aplanar configuration when laid on a flat surface.

FIG. 4F shows an isometric cross-section of a portion of the tube.

FIG. 4F-1 shows an enlarged portion of a layer of the tube.

FIG. 4F-2 shows an enlarged portion of a layer of the tube.

FIG. 4G shows a cross section of a portion of the patient interface asshown in FIG. 4C.

FIG. 4H shows a cross section of a portion of the patient interface asshown in FIG. 4C.

FIG. 4I shows a possible cross-section shape of the tube of the patientinterface.

FIG. 4J shows another possible cross-section shape of the tube of thepatient interface.

FIG. 4K shows another possible cross-section shape of the tube of thepatient interface.

FIG. 4L-1 shows an isometric view of the tube in a pre-determined threedimensional configuration.

FIG. 4L-2 is a side view of a portion of the tube.

FIG. 4L-3 is a front view of a portion of the tube.

FIG. 4L-4 is a top view of a portion of the tube.

FIG. 4M depicts isometric cutaway view of a connection port within thetube.

FIG. 4N depicts an isometric view of the connection port in isolation.

FIG. 4O depicts an isometric view of the connection portion of analternate form.

FIG. 4P depicts a connection between the mask and the tube.

FIG. 4Q depicts an alternate form of a connector for attaching the maskto the tube.

FIG. 4R shows an isometric view of a patient interface according toanother example of the present technology worn by a patient.

FIG. 4S is a perspective view of a patient interface according toanother example of the disclosed technology.

FIG. 4T is a front perspective view of an upper connector of thepositioning and stabilizing structure according to an example of thedisclosed technology.

FIG. 4U is a side perspective view of a lower connector of thepositioning and stabilizing structure according to an example of thedisclosed technology.

FIG. 4V is an illustration of a cross-section of the positioning andstabilizing structure of FIG. 4S.

FIG. 4W is an illustration of a cross-section of an outer layer of thepositioning and stabilizing structure according to another example ofthe disclosed technology.

FIG. 4X is a perspective view of a patient interface according toanother example of the disclosed technology.

FIG. 5A depicts a view of a strap of the patient interface.

FIG. 5B depicts a side view of a portion of the strap.

FIG. 5C depicts a partially exploded view of a portion of strap 3420.

FIGS. 5D and 5E depict a portion of the strap in an untensioned andtensioned state.

FIG. 5F depicts an alternate patient interface that includes analternate head strap.

FIG. 5G depicts a top view of the head strap of FIG. 5F in isolation.

FIG. 5H depicts an exploded isometric view of the head strap.

FIG. 6A depicts an isometric top view of the seal-forming structureutilized in the patient interface.

FIG. 6B depicts an isometric bottom view of the seal-forming structureof the patient interface.

FIG. 6C depicts an isometric view of a sealing layer of the seal-formingstructure.

FIG. 6D depicts a cross-sectional isometric view of the sealing layer.

FIG. 6D-1 depicts an enlarged view of a portion of the sealing layer.

FIG. 6E depicts the seal-forming structure attaching to the frame.

FIG. 7A depicts a mold for use in forming the sealing layer.

FIG. 7B depicts a textile sheet positioned to engage with the mold.

FIG. 7C depicts the textile sheet adjacent to the mold and spread on themold using a roller.

FIG. 7D depicts the textile sheet pressed into the form of the mold.

FIG. 7E depicts a membrane layer being administered to the textile sheetwithin the mold.

FIG. 7F depicts subjecting the membrane layer to heat.

FIG. 7G depicts removing the cured layer from the mold.

FIG. 7H depicts cutting the sealing forming layer to shape.

FIG. 7I depicts a planar sheet that is pre-cut prior to insertion withinthe mold.

FIG. 7J depicts the sheet after application within the mold.

FIG. 8A depicts a sheet being positioned over a mold to form a tube.

FIG. 8B depicts the sheet within the mold.

FIG. 8C depicts positioning a membrane layer to interact with the sheetwithin the mold.

FIG. 8D depicts heating the membrane layer such that the membrane layercures to the shape of the mold.

FIG. 8E depicts attaching a cured two cures sheets together.

FIG. 8F depicts a portion of a tube formed from two sheet.

FIG. 8G depicts a sheet positioned above a mold.

FIG. 8H depicts spraying a membrane layer onto the sheet while the sheetis in the mold.

FIG. 8I depicts the sheet and membrane layer within the mold.

FIG. 8J depicts removing the cured layer from the mold.

FIG. 8K depicts a tube formed from two cured layers.

FIGS. 8L and 8M depict another method for forming a tube for use in apatient interface.

FIGS. 9A and 9B depicts method for forming a tube with an alternateform.

FIG. 9C depicts a tube 3450 of an alternate form.

FIGS. 9D and 9E depict cross-sections of tube 3450 of FIG. 9C in aninflated and uninflated state.

FIG. 10 shows a perspective view of a patient interface 9000 accordingto an example of the present technology.

FIG. 11 shows a perspective view of a patient interface 10000 accordingto another example of the present technology.

FIGS. 12A and 12B are detail views of the headgear tube connectorsaccording to an example of the present technology.

FIG. 13 shows a perspective view of a gas delivery tube 9350 of apatient interface 9000 according to another example of the presenttechnology.

FIG. 14 shows a cross section view of the gas delivery tube 9350 of FIG.11.

FIG. 15 shows a cross section view of a gas delivery tube 9350 accordingto another example of the present technology.

FIG. 16 shows an illustration of a cross-section of a gas delivery tube9350 according to another example of the present technology.

FIG. 17 shows an illustration a cross-section of a non-patientcontacting portion 9349 of a gas delivery tube according to anotherexample of the present technology.

FIG. 18 shows a side view of a patient interface 9000 according toanother example of the present technology.

FIG. 19 shows a perspective view of a patient interface 9000 accordingto another example of the present technology.

FIG. 20 shows a perspective view of a patient interface 9000 accordingto another example of the present technology.

FIG. 21 shows a left side view of the patient interface 9000 of FIG. 20.

FIG. 22 shows a right side view of the patient interface 9000 of FIG.20.

FIG. 23 shows a front view of the patient interface 9000 of FIG. 20.

FIG. 24 shows a front view of a crown connector 9360 and elbow 9610 ofthe patient interface 9000 shown in FIG. 20.

FIG. 25 shows a perspective view of a crown connector 9360 of thepatient interface 9000 of FIG. 20.

FIG. 26 shows a perspective view of a headgear tube 9350 of the patientinterface 9000 of FIG. 20.

FIG. 27 shows a cross section of a superior tube portion 9304 of aheadgear tube 9350 of the patient interface 9000 of FIG. 20.

FIG. 28 shows a cross section of an inferior tube portion 9363 of aheadgear tube 9350 of the patient interface 9000 of FIG. 20.

FIG. 29 shows a cross section of a superior tube portion 9304 of aheadgear tube 9350 of the patient interface 9000 of FIG. 20 having someforces labelled.

FIG. 30 shows a tab 3320 of a headgear tube 3350 of the patientinterface 3000 of FIG. 20.

4.4 RPT Device

FIG. 31A shows an RPT device in accordance with one form of the presenttechnology.

FIG. 31B is a schematic diagram of the pneumatic path of an RPT devicein accordance with one form of the present technology. The directions ofupstream and downstream are indicated with reference to the blower andthe patient interface. The blower is defined to be upstream of thepatient interface and the patient interface is defined to be downstreamof the blower, regardless of the actual flow direction at any particularmoment. Items which are located within the pneumatic path between theblower and the patient interface are downstream of the blower andupstream of the patient interface.

FIG. 31C is a schematic diagram of the electrical components of an RPTdevice in accordance with one form of the present technology.

4.5 Humidifier

FIG. 32A shows an isometric view of a humidifier in accordance with oneform of the present technology.

FIG. 32B shows an isometric view of a humidifier in accordance with oneform of the present technology, showing a humidifier reservoir 5110removed from the humidifier reservoir dock 5130.

4.6 Conduit of the Present Technology

FIG. 33A shows a perspective view of a conduit 5600 according to anexample of the present technology.

FIG. 33B shows a plan view of a conduit 5600 according to an example ofthe present technology.

FIG. 33C shows a cross-sectional view of a conduit 5600 according to anexample of the present technology taken through line 33C-33C of FIG.33B.

FIG. 33D shows a cross-sectional view of a conduit 5600 according to anexample of the present technology taken through line 33D-33D of FIG.33B.

FIG. 33E shows a cross-sectional view of a conduit 5600 with anoval-shaped cross-section according to an example of the presenttechnology taken through line 33D-33D of FIG. 33B.

FIG. 33F shows a cross-sectional view of a conduit 5600 with a circularcross-section according to an example of the present technology takenthrough line 33D-33D of FIG. 33B.

FIG. 33G shows a cross-sectional view of a conduit 5600 with a connector5620 according to an example of the present technology taken throughline 33C-33C of FIG. 33B.

FIG. 33H shows a cross-sectional view of a conduit 5600 with a connector5620 according to an example of the present technology taken throughline 33C-33C of FIG. 33B.

DETAILED DESCRIPTION OF EXAMPLES OF THE TECHNOLOGY

Before the present technology is described in further detail, it is tobe understood that the technology is not limited to the particularexamples described herein, which may vary. It is also to be understoodthat the terminology used in this disclosure is for the purpose ofdescribing only the particular examples discussed herein, and is notintended to be limiting.

The following description is provided in relation to various exampleswhich may share one or more common characteristics and/or features. Itis to be understood that one or more features of any one example may becombinable with one or more features of another example or otherexamples. In addition, any single feature or combination of features inany of the examples may constitute a further example.

5.1 Therapy

In one form, the present technology comprises a method for treating arespiratory disorder comprising the step of applying positive pressureto the entrance of the airways of a patient 1000.

In certain examples of the present technology, a supply of air atpositive pressure is provided to the nasal passages of the patient viaone or both nares.

In certain examples of the present technology, mouth breathing islimited, restricted or prevented.

5.2 Treatment Systems

In one form, the present technology comprises an apparatus or device fortreating a respiratory disorder. The apparatus or device may comprise anRPT device 4000 for supplying pressurised air to the patient 1000 via anair circuit 4170 to a patient interface 3000.

5.3 Patient Interface

With reference to FIG. 3A, a non-invasive patient interface 3000 inaccordance with one aspect of the present technology comprises thefollowing functional aspects: a seal-forming structure 3100, a plenumchamber 3200, a positioning and stabilising structure 3300, a vent 3400,one form of connection port 3600 for connection to air circuit 4170, anda forehead support 3700. In some forms a functional aspect may beprovided by one or more physical components. In some forms, one physicalcomponent may provide one or more functional aspects. In use theseal-forming structure 3100 is arranged to surround an entrance to theairways of the patient so as to facilitate the supply of air at positivepressure to the airways.

If a patient interface is unable to comfortably deliver a minimum levelof positive pressure to the airways, the patient interface may beunsuitable for respiratory pressure therapy.

The patient interface 3000 in accordance with one form of the presenttechnology is constructed and arranged to be able to provide a supply ofair at a positive pressure of at least 6 cmH2O with respect to ambient.

The patient interface 3000 in accordance with one form of the presenttechnology is constructed and arranged to be able to provide a supply ofair at a positive pressure of at least 10 cmH2O with respect to ambient.

The patient interface 3000 in accordance with one form of the presenttechnology is constructed and arranged to be able to provide a supply ofair at a positive pressure of at least 20 cmH2O with respect to ambient.

5.3.1 Seal-Forming Structure

In one form of the present technology, a seal-forming structure 3100provides a target seal-forming region, and may additionally provide acushioning function.

The target seal-forming region is a region on the seal-forming structure3100 where sealing may occur. The region where sealing actually occurs-the actual sealing surface- may change within a given treatment session,from day to day, and from patient to patient, depending on a range offactors including for example, where the patient interface was placed onthe face, tension in the positioning and stabilising structure and theshape of a patient's face.

In one form the target seal-forming region is located on an outsidesurface of the seal-forming structure 3100. A seal-forming structure3100 in accordance with the present technology may be constructed from asoft, flexible, resilient material such as silicone or otherbiocompatible material.

In one form, the seal-forming structure includes a sealing flangeutilizing a pressure assisted sealing mechanism. In use, the sealingflange can readily respond to a system positive pressure in the interiorof the plenum chamber 3200 acting on its underside to urge it into tightsealing engagement with the face. The pressure assisted mechanism mayact in conjunction with elastic tension in the positioning andstabilising structure.

In one form, the seal-forming structure may comprise a compressionsealing portion or a gasket sealing portion. In use the compressionsealing portion, or the gasket sealing portion is constructed andarranged to be in compression, e.g. as a result of elastic tension inthe positioning and stabilising structure.

In one form, the seal-forming structure comprises a tension portion. Inuse, the tension portion is held in tension, e.g. by adjacent regions ofthe sealing flange.

In one form, the seal-forming structure comprises a region having atacky or adhesive surface.

In certain forms of the present technology, a seal-forming structure maycomprise one or more of a pressure-assisted sealing flange, acompression sealing portion, a gasket sealing portion, a tensionportion, and a portion having a tacky or adhesive surface.

The seal-forming structure 3100 may be non-invasive, i.e. does notextend internally of the patient's airways. In some forms of thetechnology, no part of the seal-forming structure 3100 enters thepatient's mouth in use. In some forms of the technology, theseal-forming structure 3100 is configured to leave the patient's mouthuncovered in use. In some forms of the technology, the seal-formingstructure 3100 does not cover the patient's eyes in use.

In one form, the seal-forming structure 3100 comprises a sealing flangeand a support flange. The sealing flange comprises a relatively thinmember with a thickness of less than about 1 mm, for example about 0.25mm to about 0.45 mm that extends around the perimeter of the plenumchamber 3200. The support flange may be relatively thicker than thesealing flange and the marginal edge of the plenum chamber 3200. Andextends at least part of the way around the perimeter. The supportflange is or includes a spring-like element and functions to support thesealing flange from buckling in use. In use the sealing flange canreadily respond to system pressure in the plenum chamber 3200 acting onits underside to urge it into tight sealing engagement with the face.

In another form, the seal-forming portion of the non-invasive patientinterface comprises a pair of nasal puffs or nasal pillows, each nasalpuff or nasal pillow being constructed and arranged to form a seal witha respective naris of the nose of a patient. Nasal pillows in accordancewith an aspect of the present technology include: a frusto-cone, atleast a portion of which forms a seal on an underside of the patient'snose, a stalk, a flexible region on the underside of the frusto-cone andconnecting the frusto-cone to the stalk. In addition, the structure towhich the nasal pillow of the present technology is connected includes aflexible region adjacent the base of the stalk. The flexible regions canact in concert to facilitate a universal joint structure that isaccommodating of relative movement both displacement and angular of thefrusto-cone and the structure to which the nasal pillow is connected.For example, the frusto-cone may be axially displaced towards thestructure to which the stalk is connected.

In one form, the seal-forming structure is configured to form a seal inuse with the underside of the nose around the nares and optionally withthe lip superior. This type of seal-forming structure may be referred toas a “nasal cradle cushion” or “sub-nasal mask”, such as seal-formingstructure 3100 of the non-invasive patient interface 3000. The shape ofthe seal-forming structure may be configured to match or closely followthe underside of the patient's nose, i.e. the profile and angle of theseal-forming structure may be substantially parallel to the patient'snaso-labial angle. In one form of nasal cradle cushion, the seal-formingstructure comprises a septum member defining two orifices, each ofwhich, in use, supply air or breathable gas to a different one of thepatient's nares. The septum member may be configured to contact or sealagainst the patient's columella in use. In some forms of the technology,the seal-forming structure 3100 is configured to form a seal on anunderside of the patient's nose without contacting a nasal bridge regionof the patient's nose. A nasal cradle interface 3000 is also shown inFIGS. 4A-4D, 10 and 11, for example. In some examples, patient interfacemay comprise a seal-forming structure 9100 in the form of a cradlecushion as described in PCT publication WO 2018/176094, filed Mar. 29,2018, the entire contents of which are incorporated herein by reference.

In one form, the non-invasive patient interface 3000 comprises aseal-forming portion that forms a seal in use on an upper lip region(that is, the lip superior), a nasal bridge region and a cheek region ofthe patient's face. This is the case, for example, with the patientinterface 3000 shown in FIG. 1B. This seal-forming portion delivers asupply of air or breathable gas to both nares of patient 1000 through asingle orifice. This type of seal-forming structure may be referred toas a “nasal cushion” or “nasal mask”. In some examples of the presenttechnology, the positioning and stabilising structure may be utilised tohold a nasal cushion in sealing position on a patient's face.

In one form the non-invasive patient interface 3000 comprises aseal-forming portion that forms a seal in use on a chin-region, a nasalbridge region and a cheek region of the patient's face. This is thecase, for example, with the patient interface 3000 shown in FIG. 1C.This seal-forming portion delivers a supply of air or breathable gas toboth nares and mouth of patient 1000 through a single orifice. This typeof seal-forming structure may be referred to as a “full-face mask”. Insome examples of the present technology, the positioning and stabilisingstructure may be utilised to hold a full-face cushion in sealingposition on a patient's face.

In another form the patient interface 3000 comprises a nasalseal-forming structure in the manner of a nasal cushion or nasal cradlecushion and an oral seal-forming structure that is configured to form aseal in use around the mouth of a patient (which may be referred to as a“mouth cushion” or “oral mask”). In such a mask air or breathable gas issupplied in use through separate orifices to the patient's nares and thepatient's mouth. This type of seal-forming structure 3100 may bereferred to as an “oronasal cushion” or “ultra-compact full facecushion”. In one form, the nasal seal- forming structure and oralseal-forming structure are integrally formed as a single component. Insome examples, patient interface may comprise a seal-forming structurein the form of a cradle cushion as described in U.S. Patent ApplicationNo. 62/649,376 (corresponding to PCT Application No. PCT/AU2019/050278,filed Mar. 28, 2019), the entire contents of which are incorporatedherein by reference. In some examples of the present technology, thepositioning and stabilising structure of a patient interface may beutilised to hold an oronasal cushion in sealing position on a patient'sface.

In some examples of the present technology, the plenum chamber 3200 hasa perimeter that is shaped to be complementary to the surface contour ofthe face of an average person in the region where a seal will form inuse. In use, a marginal edge of the plenum chamber is positioned inclose proximity to an adjacent surface of the face. Actual contact withthe face is provided by the seal-forming structure. The seal-formingstructure may extend in use about the entire perimeter of the plenumchamber. In some forms, the plenum chamber and the seal-formingstructure are formed from a single homogeneous piece of material.

In certain forms of the present technology, the plenum chamber does notcover the eyes of the patient in use. In other words, the eyes areoutside the pressurised volume defined by the plenum chamber. Such formstend to be less obtrusive and/or more comfortable for the wearer, whichcan improve compliance with therapy.

In certain forms of the present technology, the plenum chamber isconstructed from a transparent material, e.g. a transparentpolycarbonate. The use of a transparent material can reduce theobtrusiveness of the patient interface, and help improve compliance withtherapy. The use of a transparent material can aid a clinician toobserve how the patient interface is located and functioning.

In certain forms of the present technology, the plenum chamber isconstructed from a translucent material. The use of a translucentmaterial can reduce the obtrusiveness of the patient interface, and helpimprove compliance with therapy.

In some forms of the technology, the seal-forming structure 3100 isconfigured so that the seal-forming structure does not extend below amental protuberance region of the patient's head in use.

Unless clearly specified otherwise, embodiments of patient interfaceaccording to the present technology may comprise any of the above typesof seal-forming structures.

5.3.2 Seal-Forming Structure Configuration

In some forms of the present technology, the seal-forming structure 3100(also referred to as a cushioning structure, conforming structure, orinterfacing structure) is constructed of a fabric or textile material.For example, seal-forming structure 3100 may be woven, non-woven, knit,or any other network of fibers. A seal-forming structure 3100 formedfrom a textile material may increase the comfort and feel of the sealforming structure against the face of a patient. Increased comfort mayincrease the likelihood that a patient may continue to utilize theapparatus to receive therapy.

These sealing structures may be utilized to form a surface to pressagainst the face of a patient to deliver air to the nose and/or mouth ofa patient. Some patients may appreciate the feeling of a textilematerial against his or her face as opposed to silicone or othermaterial. A sealing structure may be formed using similar techniques andmethods as described later in this detailed description with referenceto tubes and air delivery system. For example, a cut and seal method maybe utilized as well as a laying-up method.

In use, various components may be formed using such a technique. In someforms a mask component of a therapy device may be formed using a lay-upmethod of manufacturing. In one form, a releasing agent is placed on themold. Next a layer for use in the mask is placed within the mold. Thelayer may be formed of various materials. In some forms the layer may bea cloth type material. In other forms, the layer may be plastic,thermoplastic, rubber, silicone or other bendable or pliable material.

Referring to FIGS. 6A and 6B, a seal forming structure that incorporatesa textile is depicted. As shown, seal-forming structure 3100 includessealing layer 3102 and base 3104. Sealing layer 3102 may be secured tobase 3104 so that the entire seal-forming structure 3100 may be attachedto a receiving receptacle that is attached to a supply conduit such astube 3350. As shown, sealing layer 3102 includes a pre-definedthree-dimensional shape. This pre-defined three-dimensional shape isachieved without the aid of air pressure or additional supportstructures beyond the material of sealing layer 3102 itself. Thepre-defined three-dimensional shape is defined not by the thickness ofthe material from which sealing layer 3102 is formed, but the geometricpositions of the various portions of sealing layer 3102. For example,the material from which sealing layer 3102 bends into various planes,and is configured to maintain its shape within these various planes.

As shown in FIGS. 6A-6E, sealing layer 3102 may be formed toparticularly interact and engage with the nasal area of a patient. Whenworn by a patient the upper surface of sealing layer 3102 may beconfigured to engage with particular portions of the face of thepatient. For example, portions adjacent first naris opening 3108 andsecond naris opening 3110 may be configured to engage the alar of thepatient, whereas saddle region 3109 may be spaced from the columella ofthe patient. Further, naso-labial sulcus engagement area 3106 may beshaped to engage with the naso-labial sulcus of the patient. Further,seal-forming structure 3100 is configured such that the mouth of thepatient is free from obstruction by seal-forming structure 3100 suchthat the patient is able to breathe through his or her mouth withoutpressurized air passing through the mouth of the patient. Additionally,as shown in FIGS. 6A-6E, sealing layer 3102 is formed such that sealinglayer 3102 does not extend over the bridge of the nose. For example,when used, at least the lateral cartilage portion, nasal bones, andseptal cartilage are not covered by sealing layer 3102 (see FIG. 2L).

Although air pressure is not necessary to support the shape of sealinglayer 3102 in some forms, portions of sealing layer 3102 may be enhanceswith air pressure to contribute to a good seal between sealing layer3102 and the patient's face. For example, in some forms, aconcertina-shaped portion of sealing layer 3102 may be formed adjacentbase 3104. When pressurized the concertina portion may expand therebyproviding additional sealing pressure between sealing layer 3102 and theface of the patient. Further, other portions of sealing layer 3102 maybe configured to expand to engage with a particular area of the patientsface, for example the nasolabial sulcus.

Sealing layer 3102 may be deformable such that when pressed with anormal amount of force when used with patient interface 3000, sealinglayer 3102 deforms. Sealing layer 3102 may conform to the shape ofvarious portions of the face of the patient such that air leakage isminimized. Once removed from a patient's face, sealing layer 3102 mayresiliently return to its pre-deformed shape. That is, sealing layer3102 has a 3-dimensional shape when not pressurized that sealing layer3102 returns to once force is released from sealing layer 3102.

Sealing layer 3102 may be formed of various layers such that sealinglayer 3102 is a laminate structure. Each of the layers may impart aparticular property to sealing layer 3102. In one form of the presenttechnology, sealing layer 3102 includes thermoplastic or thermosetmaterial. This material is able to maintain a particular shape oncecured in such a shape. For example, in one form, sealing layer 3102 mayinclude a thermoset material such as a foam material. This thermosetmaterial may conform to a mold and retain the shape of the mold as shownin FIGS. 7A-7H.

Sealing layer 3102 may be configured to press against particular areasof a nose or nasal area. For example, naso-labial sulcus area 3106 maybe configured to press against the naso-labial sulcus region of apatient. Additionally, other areas of sealing layer 3102 may beparticularly shaped to correspond to the face of a patient. Sealinglayer 3102 includes a first naris opening 3108 and second naris opening3110 that are configured to align with each naris of a patient. Further,sealing layer 3102 includes a saddle region 3109 that is located betweeneach of the first naris opening 3108 and second naris opening 3110. Thesaddle region 3109 extends away from the columella of the user when isuse such that the material of sealing layer 3102 is spaced from the noseof a patient to increase comfort.

Sealing layer 3102 may also be particularly shaped such that the surfacethat seals to the patient's face is spaced from base 3104. By spacingsealing layer 3102 from base 3104 a cushioning zone, or a buffer zonebetween the softer surface of sealing layer 3102 and the hardcomposition of the base 3104 may be formed. For example, as shown inFIG. 6D, sealing layer 3102 has a height 3111 that spaces the engagingsurface of sealing layer 3102 from other components of patient interface3000. In addition to having a height 3111, as shown throughout thefigures, sealing layer 3102 may have various areas that have positiveand negative curvatures, saddle regions, and domes, in addition to otherconfigurations. The particular shapes of sealing layer may be formed toengage with the airways of a patient. These particular shapes may beformed using a mold with a complex shape or other technique as describedin this detailed description.

In some forms, first naris opening 3108 and second naris opening 3110may be raised from the surrounding surfaces. That is, in some forms thematerial around first naris opening 3108 and second naris opening 3110include flanges 3107 that extend away from the surface of seal layer3102 toward the nares of a user. By elevating particular areas of seallayer 3102 a better or more secure fit may be achieved over other formsof the technology. For example, first naris opening 3108 and secondnaris opening 3110 may engage with the nasal walls corresponding to thecolumella, the alar, or other portions of the nasal opening. The flanges3107 may provide stability such that the first naris opening 3108 andthe second naris opening 3110 may be restricted from moving away fromthe nasal openings. This alignment provided by first naris opening 3108and second naris opening 3110 may provide consistent application ofoxygen to the patient. In some forms, the shape of the first narisopening 3108 and the second naris opening 3110 may have a substantiallyfrustoconical shape. In other forms, the shape of the openings may nottaper as in a frustoconical shape, but rather flanges 3107 may extendvertically. In still other forms, the shape of the openings may beformed to engage with the interior surfaces of the nasal openings. Instill other forms, the material around first naris opening 3108 andsecond naris opening 3110 may be evenly aligned with the surroundingmaterial of sealing layer 3102.

Further, the height or depth of the flanges 3107 of the first narisopening 3108 and second naris opening 3110 may be particularly formed.Some patients may prefer a configuration such that the openings extend alarger distance into the nares of the patient when compared to otherpatients. The depth of the flanges 3107 of the first naris opening 3108and the second naris opening 3110 may therefore be adjusted depending onthe preference of the patient or the medical professional. The flanges3107 may be formed in a similar manner as the rest of seal formingstructure 3102 in that a foam or thermoset material may be utilized tomaintain the shape of the flange even without air pressure or otherrigid type of material. The shape of the naris may also depend on theshape of the mold used to form the seal layer 102, as shown in FIGS.7A-7H.

In some forms, sealing layer 3102 may be particularly arranged toinclude more rigid and less rigid areas that correspond to particularareas of a patient. Sealing layer 3102 may include more rigid or stiffportions along naso-labial sulcus area 3106 where sealing layer 3102 isconfigured to engage with the naso-labial sulcus of a patient. This areaof the face is less sensitive that other areas of the face and thereforethicker or more rigid portions may be utilized to provide a sturdystructure for sealing. Other areas of sealing layer 3102 may includemore floppy or less rigid structures. For example, flanges 3107 ofsealing layer 3102 that may contact the columella of a patient may beless rigid so as to not disturb a patient.

In some forms, the rigidity or stiffness of the sealing layer 3102 maybe altered or determined by the amount or quantity of membrane material,such as a thermoplastic material that is applied on an interior surfaceof the sealing layer 3102. In other forms, the rigidity or stiffness ofsealing layer 3102 may be determined based on the quantity of materialutilized. For example, in some forms, sealing layer 3102 includes bendsor folds which increase the thickness or density of sealing layer 3102at particular locations. By folding the material of sealing layer 3102in a particular manner, therefore, additional membrane material orsupport may not be necessary to form rigid areas of sealing layer 3102.

Sealing layer 3102 may be secured to base 3104. Base 3104 may include aclip such that seal-forming structure 3100 is easily removable from areceiving receptacle such as frame 3152 of patient interface 3000 (See,e.g. FIG. 6E). Additionally, base 3104 may be stiffer or more rigid thatsealing layer 3102. Base 3104 may therefore resist bending along an edgeof sealing layer 3102 such that when sealing layer 3102 of seal-formingstructure 3100 is depressed the sides of sealing layer 3102 remain in asecured location.

Additionally, other forms of sealing layer 3102 may be utilized. Forexample, in some forms a full mask may be utilized rather than sealingstructure that only provides air to the nose. In other forms, a maskthat provides air solely to the mouth may be utilized. Variousconfigurations may also be utilized. For example, in some forms a singlehole or aperture may be utilized rather than separate holes for eachnaris. Further, in some forms the sealing structure may be designed toaccept a nose whereas in other designs the sealing structure may bedesigned to abut against surfaces of the nose without enveloping orsurrounding the nose. Additionally, the masks or sealing structures maybe designed for particular comfort. For example, in some forms a nasalmask may be designed such that the tip or pronasale of the patient isspaced from the mask. The pronasale is generally a sensitive area of thenose and therefore designing a mask such that the pronasale is spacedfrom the mask may increase comfort of a patient.

A cross-section of sealing layer 3102 is depicted in FIG. 6D and anenlarged view of a portion of sealing layer 3102 is depicted in FIG.6D-1. As shown, membrane layer 3118 is located along an inner surface ofsealing layer 3102. Textile sheet 3116 is located along a lower oppositesurface of sealing layer 3102. The thickness of membrane layer 3118 maybe determined or altered during the manufacturing process depending onthe manufacturing requirements. For example, a thicker membrane layer3118 may provide more rigidity than a thinner membrane layer 3118. Athinner membrane layer 3118 may allow for sealing layer 3102 to be moreable to adapt to the face of a patient. In some forms, the thickness ofsealing layer 3102 is only determined by the thickness of membrane layer3118 and textile sheet 3116. That is, in some forms, no other extracomponents such as rigidizers are used to maintain the shape of sealinglayer 3102. For example, sealing layer 3102 may be easily deformablealong all portions of sealing layer 3102.

As described previously, naso-labial sulcus engagement area 3107 mayhave a different thickness of material than adjacent portions of sealinglayer 3102. For example, a greater amount of a membrane layer may beapplied along the interior surface of sealing layer 3102 at naso-labialsulcus engagement area 3107. This additional material may increase thethickness and rigidity of the naso-labial sulcus engagement area 3107.

In addition to providing structure and support to sealing layer 3102,membrane layer 3118 may also contain air within sealing layer 3102. Thatis, in some forms, membrane layer 3118 may prevent air from passingthrough the material of sealing layer 3102. Membrane layer 3118 maytherefore direct or air from a therapy device to the naris openings ofsealing layer 3102 and to the patient. Further, as described later inother forms, sealing layer 3102 may be designed to allow for particularleak rates such that a separate bleed or leak valve may not benecessary. This feature may therefore reduce the costs of manufacturingby removing a component from therapy device.

In some forms, membrane layer 3118 may be a meltable material such as athermoplastic material or thermoset material. This material may be ableto assume a shape when melted into a mold or other form. As detailedlater in this specification and shown in FIGS. 7A-7H membrane layer 3118may be melted or partially melted (for example, tacky) such that thematerial is able to conform to a particular shape. Once the membranelayer 3118 is melted, it is allowed to cure to shape (such as the shapeof a mold). Once cured, membrane layer 3118 assumes the shape of themold such that membrane layer 3118 has a predetermined shape. Membranelayer 3118 imparts that shape onto whatever material membrane layer 3118is laminated or adhered to. For example, membrane layer 3118 may causetextile sheet 3116 to assume the same shape as membrane layer 3118because membrane layer 3118 is secured with textile sheet 3116 as isable to conform to various shapes. Textile sheet 3116 may also includesuch characteristics such that textile sheet 3116 includes portions thatmay be meltable and then conformable to a shape. The amount of pressurerequired to temporarily alter the shape of the laminate of sealing layer3102 may depend on the thickness of membrane layer 3118 and from whatmaterial membrane layer 3118 is formed.

In some forms of the present technology, membrane layer 3118 may beformed of a thermoset material. Additionally, sealing layer 3102 mayinclude an additional laminated layer that is formed of a thermosetmaterial. An example of a thermoset material is a foam. The laminatewith the thermoset material can be placed in a mold and then subjectedto heat. The thermoset material may be cured in a similar manner to thethermoplastic material. That is, the thermoset material may be subjectedto heat, and, unlike thermoplastic materials, the thermoset material mayirreversibly cure to a particular shape. The thermoset material may beused if a more rigid or permanent structure as desired. The flexibilityand stiffness of the component, such as sealing layer 3102 may beadjusted based on the material selected and thickness of the thermosetmaterial. Because the thermoset material can be cured to a particularshape, when used as a laminate with sealing layer 3102, the shape ofsealing layer 3102 may also be formed to a particular shape.

Referring to FIG. 4P, sealing layer 3102 along with base 3104 and frame3152 may be incorporated into a mask and air delivery system for usewith a therapy. As shown, base 3104 may be attached to assemblyconnection port 3154. Assembly connection port 3154 may provide airdistribution to sealing layer 3102 through tube 3350.

Sealing layer 3102 may be lighter than other forms of the technology andalso may be more comfortable to a patient than other forms of thetechnology. Further, because textile sheets such as textile sheet 3116may be stored in a flat or planar manner, the storage costs for thematerials may be less than other forms. Additionally, use of mold 3112(see FIGS. 7A-7G) may permit complex shapes to be formed such as sealinglayer 3102 while reducing costs. Rather than utilizing injection moldingor extrusion molding that requires multiple complex pieces andmachinery, the laying up process that includes a mold such as mold 3112provides a simple process that may reduce manufacturing time as well ascosts. Additionally, complex shapes may be formed with relative ease.

Further, in some forms, membrane layer 3118 utilized in forming sealinglayer 3102 may be the same material as utilized in forming textiletubing as described later in this detailed description. By using thesame material, production costs for various components may be reducedbecause a large quantity of material may be able to be purchased inbulk.

Referring to FIG. 4Q, a possible assembly of a portion of a tube that isconfigured to interact with sealing-forming structure 3100 is depicted.As shown, assembly connection port 3154 is secured between layers of thetube. Assembly connection port 3154 is sandwiched between an innertextile layer 3452 and outer textile layer 3454. Further, assemblyconnection port 3154 extends through exterior foam layer 3456. In thisconfiguration, a air passageway or air conduit is formed between innertextile layer 3452 and outer textile layer 3454 such that assemblyconnection port 3154 is used to transfer air from the air passageway andthrough exterior foam layer 3456. In this manner assembly connectionport 3154 is secured by inner textile layer 3452 and outer textile layer3454. Connection port 3154 may then be snap fitted, friction fit, orotherwise secured to frame 3152 to provide air to the patient.

5.3.2.1 Method of Forming Seal Forming Structure

Referring to FIGS. 7A-7J one method of forming a sealing structure isshown. In FIG. 7A, mold 3112 includes accommodating portion 3114.Accommodating portion 3114 may be in the shape of a sealing surface usedin conjunction with a full face, nose, or other mask as utilized with atherapy device.

Referring to FIGS. 7B and 7C, a textile sheet 3116 is placed over mold3112. Textile sheet 3116 may be formed of materials as such as cotton,polyester, rayon, or other materials or a combination of materials.Further, the configuration of textile sheet 3116 may also be formed inthe same type of configuration as with respect to sheets described indetail below such as inner layer 3352 and outer layer 3426. That is,textile sheet 3116 may be woven, non-woven, knit, braided, or any othernetwork of fibers. Although not depicted in FIGS. 7A-7H as including atextile membrane before being placed in accommodating portion 3114 ofmold 3112, in other forms textile sheet 3116 may include a textilemembrane. In still further forms, textile sheet 3116 may bepre-laminated with textile sheet 3116 such as with polyurethane orsilicone.

After arranging textile sheet 3116 along mold 3112, textile sheet 3116may be pressed into place within accommodating portion 3114. In someforms, a roller may be used to ensure that textile sheet 3116 is in thecorrect position as depicted in FIGS. 7C and 7D. In other forms, avacuum seal may be utilized that pulls textile sheet 3116 towardaccommodating portion 3114. In still other forms, another form may beutilized that presses textile sheet 3116 into accommodating portion3114.

Once textile sheet 3116 is in place, as shown in FIG. 7E, a membranematerial may be placed along an upper surface of textile sheet 3116.Membrane layer 3118 may be thermoplastic or thermoset material,silicone, polyurethane, or other material. The material of membranelayer 3118 may be sprayed on as depicted, may be painted or spread on,or may be pre-laminated on textile sheet 3116. Membrane layer 3118 maybe a resin or other material that cures or solidifies through a chemicalprocess or by exposure to air. As shown, membrane layer 3118 is a liquidthermoset material. Membrane layer 3118 is spread along the uppersurface covering surfaces as required by the manufacturer. In someforms, the entire upper surface of textile sheet 3116 may not becovered. That is, in some instances, portions of textile sheet 3116 mayremain uncovered to provide easier attachment or securement with othercomponents. Further, in other forms, textile sheet 3116 may be alaminate and already include a surface that is formed of a membranematerial.

Further, membrane layer 3118 may be thicker in some areas when comparedto other areas. Membrane layer 3118 may be administered at differentrates in a liquid form to provide different thicknesses. Further,membrane layer 3118 when formed as an independent solid layer, may bepre-manufactured to have thicker regions in some areas (for example,naso-labial sulcus engagement area 3107) than other areas (for example,flanges 3107).

Referring to FIG. 7F, membrane layer 3118 and textile sheet 3116 may beexposed to heat. The heat may melt membrane layer 3118 if membranematerial has solidified and may also allow membrane layer 3118 to beconsistently spread or layered along textile sheet 3116. In other forms,membrane layer 3118 may be allowed to solidify after the step shown inFIG. 7E, without adding any additional heat to the system.

After membrane layer 3118 has solidified, textile sheet 3116 along withthe cured membrane layer 3118 is removed from mold 3112 as shown in FIG.7G. Textile sheet 3116 that was located within accommodating portion3114 now assumes the shape of accommodating portion 3114 even whenremoved from accommodating portion 3114. Because membrane layer 3118 isa thermoset material that is curable to a particular shape, sealinglayer 3102 also assumes the same shape as membrane layer 3118.

As shown in FIG. 7H, sealing layer 3102 is cut away from the rest oftextile sheet 3116. As depicted, sealing layer 3102 is cut away usingscissors or shears, however in other forms sealing layer 3102 may be cutusing other techniques or devices such as die-cut. In a non-limitingexample, in some forms a hot knife may be used to cut away sealing layer3102. In other forms, a stamp may be utilized to cut through textilesheet 3116.

As shown (See FIGS. 6A-6C), first naris opening 3108 and second narisopening 3110 may be formed within sealing layer 3102. First narisopening 3108 and second naris opening 3110 may be formed withinaccommodating portion 3114. That is, accommodating portion 3114 may beshaped such that peaks or valleys are utilized to affect the topographyof the accommodating portion 3114. By altering the shape ofaccommodating portion 3114 various shapes of sealing layer 3102 may bepossible. In some forms, textile sheet 3116 may be pre-cut along theareas of accommodating portion 3114 that correspond with first narisopening 3108 and second naris opening 3110. In other forms, once cured,the material of sealing layer 3102 may be cut away in the area in whichfirst naris opening 3108 and second naris opening 3110 are to belocated. Additionally, other post-processing may be performed on sealinglayer 3102 after sealing layer 3102 is removed from mold 3112.

In some forms, textile sheet 3116 may be pre-cut prior to placingtextile sheet 3116 over mold 3112. In such forms the number of foldswithin sealing layer 3102 of seal-forming structure 3100 may be reducedwhen compared to other forms. For example as shown in FIG. 71, textilesheet 3116 is cut to form pre-cut sheet 3117. Pre-cut sheet 3117includes various notches 3120. These notches 3120 are particularlyformed such that when pre-cut sheet 3117 is placed within mold 3112 thematerial of pre-cut sheet 3117 is able to fold and not overlap withitself. That is, pre-cut sheet 3117 may be able to form abutting jointsas opposed to overlapping joints. This may improve comfort and feel tothe user. As shown in FIG. 71 for example, notch 3122 is formed betweenfirst flap 3124 and second flap 3126 of pre-cut sheet 3117. The lengthof first flap 3124 and second flap 3126 may be used to determine theheight 3111 of the sealing layer 3102.

Referring now to FIG. 7J, after sheet 3117 has been placed in a mold andcured with a membrane, the first flap 3124 and second flap 3126 may befolded upwards in accordance with the mold shape. When folded, firstflap 3124 and second flap 3126 may abut each other in the area of notch3122. Based on the geometry of sealing layer 3102, the shape and size ofnotch 3122 may be altered to allow for various designs andconfigurations. As shown in FIG. 7J, first flap 3124 and second flap3126 do not overlap one another. In other forms, however, the flaps maybe designed to overlap each other to provide increased stiffness inparticular areas (for example, naso-labial sulcus engagement area 3107).

The configuration as shown in FIGS. 71 and 7J may provide for a smoothinner and outer surface of sealing layer 3102. Further, by cuttingtextile sheet prior to molding, the quantity of time used to arrange thetextile sheet within the mold may be reduced when compared to otherforms in which the textile sheet may be folded to fit within the mold.

5.3.3 Positioning and Stabilising Structure

The seal-forming structure 3100, 9100 of the patient interface 3000,6000, 7000, 8000, 9000, 10000 of the present technology may be held insealing position in use by the positioning and stabilising structure3300, 7300, 8300, 9300. The positioning and stabilising structure mayinclude or be referred to as “headgear” since it engages the patient'shead in order to hold the patient interface in a sealing position.

In one form the positioning and stabilising structure provides aretention force at least sufficient to overcome the effect of thepositive pressure in the plenum chamber 3200, 9200 to lift off the face.

In one form the positioning and stabilising structure provides aretention force to overcome the effect of the gravitational force on thepatient interface.

In one form the positioning and stabilising structure provides aretention force as a safety margin to overcome the potential effect ofdisrupting forces on the patient interface, such as from tube drag, oraccidental interference with the patient interface.

In one form of the present technology, a positioning and stabilizingstructure is provided that is configured in a manner consistent withbeing worn by a patient while sleeping. In one example the positioningand stabilising structure has a low profile, or cross-sectionalthickness, to reduce the perceived or actual bulk of the apparatus. Inone example, the positioning and stabilising structure comprises atleast one strap having a rectangular cross-section. In one example thepositioning and stabilising structure comprises at least one flat strap.

In one form of the present technology, a positioning and stabilisingstructure is provided that is configured so as not to be too large andbulky to prevent the patient from lying in a supine sleeping positionwith a back region of the patient's head on a pillow.

The positioning and stabilising structure may comprise at least one tie.A tie will be understood to be a structure designed to resist tension.In use, a tie is part of the positioning and stabilising structure thatis under tension. Some ties will impart an elastic force as a result ofthis tension, as will be described. A tie may act to maintain theseal-forming structure in a therapeutically effective position on thepatient's head. In certain forms of the present technology, thepositioning and stabilising structure may comprise ties in the form ofheadgear tube and/or headgear straps, as will now be described.

In one form of the present technology, the positioning and stabilisingstructure comprises a first tie, the first tie being constructed andarranged so that in use at least a portion of an inferior edge thereofpasses superior to an otobasion superior of the patient's head andoverlays a portion of the parietal bone without overlaying the occipitalbone. The first tie may be provided, for example, as part of a patientinterface that comprises a cradle cushion, nasal pillows, nasal cushion,full-face cushion or an oronasal cushion. For example, the positioningand stabilising structures may comprise a first tie in the form of gasdelivery tubes which lie over the top of the patient's head. The gasdelivery tubes may also be known as headgear tubes as they providefunctions of headgear.

In one form of the present technology suitable for a nasal-only mask orfor a full-face mask, the positioning and stabilising structure includesa second tie, the second tie being constructed and arranged so that inuse at least a portion of a superior edge thereof passes inferior to anotobasion inferior of the patient's head and overlays or lies inferiorto the occipital bone of the patient's head. The second tie may beprovided, for example, as part of a patient interface that comprises acradle cushion, nasal pillows, full-face cushion, nasal cushion or anoronasal cushion. For example, the positioning and stabilisingstructures may comprise a second tie in the form of a strap that liesagainst posterior surfaces of the patient's head.

In one form of the present technology suitable for a nasal-only mask orfor a full-face mask or oronasal mask, the positioning and stabilisingstructure includes a third tie that is configured to anchor againstposterior surfaces of the patient's neck. Additionally, in some formsthe positioning and stabilising structure comprises a fourth tie that isconstructed and arranged to interconnect the second tie and the thirdtie to reduce a tendency of the second tie and the third tie to moveapart from one another.

In certain forms of the present technology, a positioning andstabilising structure comprises a strap that is bendable and e.g.non-rigid. An advantage of this aspect is that the strap is morecomfortable for a patient to lie upon while the patient is sleeping. Thepositioning and stabilising structures may comprise a strap that isbendable. The strap may be considered a backstrap. The strap issufficiently flexible to pass around the back of the patient's head andlie comfortably against the patient's head, even when under tension inuse.

In certain forms of the present technology, a positioning andstabilising structure comprises a strap constructed to be breathable toallow moisture vapour to be transmitted through the strap.

In certain forms of the present technology, a system is providedcomprising more than one positioning and stabilizing structure, eachbeing configured to provide a retaining force to correspond to adifferent size and/or shape range. For example the system may compriseone form of positioning and stabilizing structure suitable for a largesized head, but not a small sized head, and another suitable for a smallsized head, but not a large sized head.

In certain forms, the positioning and stabilizing structure may includea gas delivery tube to convey pressurized breathable gas to a patient'sairways via a mask interface (e.g., cushion module) and therefore may bereferred to as “conduit headgear.”

Referring to FIG. 4B, for example, a patient interface is shown. Asshown, patient interface 3000 includes gas delivery tube depicted astube 3350 that extends around the head of the patient along the parietalbone, above the ear and to the seal-forming structure 3100. Tube 3350may deliver air to seal-forming structure 3100 and support seal-formingstructure 3100 in place. Therefore, tube 3350 may be utilized as both asupport structure as well as an air conduit. For example, in otherforms, a separate tube, such as air delivery tube 3348 may be directlyattached to seal-forming structure 3100 and not extend around the headof the patient. In such forms the tube is not supported by the head ofthe patient, and the tube also does not provide support to the sealingstructure. Such forms also include a separate strap for support thesealing structure.

Patient interface 3000 includes head strap 3420 that is attached to tube3350 of patient interface 3000. Head strap 3420 may be utilized tosupport tube 3350 as well as assist in providing correct positioning ofpatient interface 3000. Head strap 3420 may provide tension upon tube3350 so that tube 3350 does not fall forward or anterior the face of thepatient during normal use. Additionally, head strap 3420 may work inconjunction with tube 3350 to provide sufficient upward force to sealingstructure 3100 to assist in maintaining sealing structure 3100 incorrect position with respect to the face of the patient such that thesealing layer 3102 adequately seals to the air opening of the patient.Therefore, stabilizing structure 3300 may comprise at least tube 3350 aswell as head strap 3420.

In some forms, head strap 3420 may be directly and permanently attachedto tube 3350. That is, removing head strap 3420 from tube 3350 woulddamage either or both of head strap 3420 and tube 3350. As shown in FIG.5A, head strap 3420 is directly attached to tube 3350 between an innerand outer layer of tube 3350. In some forms, head strap 3420 does notrequire stitching. For example, in some forms, head strap 3420 issandwiched between the inner and outer layer of tube 3350 and the areais subjected to heat. The inner and outer layer of tube 3350 may includea thermoplastic or thermoset material that is altered when subjected toheat. Therefore, when heated, the material may melt or soften such thatthe material interacts with head strap 3420 and when the materialsolidifies the head strap 3420 is secured between the tabs of tube 3350.In other forms, the head strap 3420 may include removably attachableportions, such as hook and loop fasteners. In such forms the tube 3350may include a slot through which head strap 3420 may pass. Then apatient may adjust the fit of patient interface 3000 by displacing thetabs of head strap 3420 and securing the strap in place. In other forms,a adjustable string, or rope, or line may be utilized to fit patientinterface 3000 comfortably on the head of the patient.

As shown, the seal-forming structure 3100 extends to the nose of thepatient while leaving the mouth free from obstruction. Some patients mayprefer a patent interface that includes a particular type of mask, suchas depicted in FIGS. 4A-4D, so that the patient may be able to conversewhile receiving therapy. Other patients may prefer a full mask or a maskthat encompasses the mouth depending on need or comfort. Various formsof the present technology may be utilized depending on the particularusage of the patient. Although depicted as a nasal mask, full face masksmay also be utilized.

In some forms the sealing structure includes a base 3104 so thatseal-forming structure 3100 may be removably attached to a frame 3152.Base 3104 may include a clip mechanism so that seal-forming structure3100 is able to be attached to frame 3152 (See FIG. 4P). Frame 3152 mayinclude attachment points or locations to which tube 3350 is attachable.Therefore, air may enter into frame 3152 and then pass to seal-formingstructure 3100 and finally to the patient.

In other forms, different frames may be utilized. For example, in someforms, the frame may include various slots or attachment points suchthat the frame is able to interact with straps such as straps from headstrap 3432. For example, although not shown in FIG. 4A, a frame mayinclude a forehead support that includes slots for interacting with astrap. Additionally, as depicted in FIG. 5F lower slots adjacent to astructure such as seal-forming structure 3100 may be utilized tointeract with a head strap and allow for adjustable fit of the head gearor stabilizing structure 3300.

In one form of the present technology, a positioning and stabilisingstructure 3300, 7300, 8300, 9300 is provided with a decoupling portionlocated between an anterior portion of the positioning and stabilisingstructure, and a posterior portion of the positioning and stabilisingstructure. The decoupling portion does not resist compression and maybe, e.g. a flexible or floppy strap. The decoupling portion isconstructed and arranged so that when the patient lies with their headon a pillow, the presence of the decoupling portion prevents a force onthe posterior portion from being transmitted along the positioning andstabilising structure and disrupting the seal.

In one form of the present technology, a positioning and stabilisingstructure comprises a strap constructed from a laminate of a fabricpatient-inner layer, a foam inner layer and a fabric outer layer. In oneform, the foam is porous to allow moisture, (e.g., sweat), to passthrough the strap. In one form, the fabric outer layer comprises loopmaterial to engage with a hook material portion.

In certain forms of the present technology, a positioning andstabilising structure comprises a strap that is extensible, e.g.resiliently extensible. For example the strap may be configured in useto be in tension, and to direct a force to draw a seal-forming structureinto sealing contact with a portion of a patient's face. In an examplethe strap may be configured as a tie.

5.3.3.1 Positioning and Stabilising Structure According to Examples ofthe Present Technology 5.3.3.1.1 Headgear Tubing

In the form of the present technology illustrated in FIG. 4B, thepatient interface 3000 includes at least one tube 3350 that deliverspressurized air received from a conduit such as air delivery tube 3348forming part of the air circuit 4170 from the RPT device to thepatient's airways. For example, through the plenum chamber 3200 andseal-forming structure 3100. The tube 3350 is an integral part of theheadgear 3300 of patient interface 3000 to position and stabilize theseal-forming structure 3100 of the patient interface to the appropriatepart of the patient's face (for example, the nose and/or mouth). Thisallows air delivery tube 3348 that provides the flow of pressurized airto connect to a connection port 3600 of the of the patient interface ina position other than in front of the patient's face, which may beunsightly to some people.

Since air can be contained and passed through tube 3350 in order todeliver pressurized air from the air circuit 4170 to the patient'sairways, the positioning and stabilizing structure 3300 may be describedas being air tight or air retaining. It will be understood that an airtight or air retaining positioning and stabilizing structure 3300 doesnot require all components of the positioning and stabilizing structure3300 to be air tight.

In certain forms of the present technology, the patient interface 3000may comprise a connection port 3600 located proximal a top, side or rearportion of a patient's head. For example, in the form of the presenttechnology illustrated in FIG. 4B, the connection port 3600 is locatedon top of the patient's head when in use. Patient interfaces in whichthe connection port is not positioned in front of the patient's face maybe advantageous as some patients find a conduit that connects to apatient interface in front of the face to be unsightly and obtrusive.For example, a conduit connecting to a patient interface in front of theface may be prone to being tangled up in bedclothes or bed linen,particularly if the conduit extends downwardly from the patientinterface in use. Forms of the technology with a patient interface witha connection port positioned proximate the top of the patient's head inuse may make it easier or more comfortable for a patient to lie or sleepin one or more of the following positions: in a side or lateralposition; in a supine position (i.e. on their back, facing generallyupwards); and in a prone position (i.e. on their front, facing generallydownwards). Moreover, connecting a conduit to the front of a patientinterface may also cause a problem known as tube drag, wherein theconduit may provide an undesired drag force upon the patient interfacethereby causing dislodgement away from the face.

In the example of FIGS. 4A, 4B-4D, the at least one tube 3350 extendsbetween the cushion assembly 3150 from the connection port 3600 acrossthe patient's cheek region and above the patient's ear, i.e. a portionof tube 3350 that connects to cushion assembly 3150 overlays a maxillaregion of the patient's head in use and a portion of tube 3350 overlaysa region of the patient's head superior to the otobasion superior of thepatient's head. Additionally, in some forms such as shown in FIGS. 4A,and 4B-4D, tube 3350 is located along both sides of the face of a user.That is, for example, tube 3350 extends across a right and left cheekregion of the patient.

In the form of the present technology illustrated in FIG. 4B, thepositioning and stabilising structure 3300 comprises a single tube 3350,that includes a right and left portion, each portion being positioned inuse on different sides of the patient's head and extending across therespective cheek region, above the respective ear (superior to theotobasion superior on the patient's head) to the connection port 3600 ontop of the patient's head. The form of technology may be advantageousbecause, if a patient sleeps on the side of their head and one of thetubes in compressed to block or partially block the flow of gas alongthe tube, the other tube remains open to supply pressurised gas to thepatient. In other embodiments of the technology, the patient interfacemay comprise a different number of tubes, for example one tube, or threeor more tubes.

As depicted in FIG. 4B the patient interface has one tube 3350. Thesingle tube 3350 is positioned on one side of the patient's head in use(e.g. across one cheek region) and head strap 3420 forms part of thepositioning and stabilising structure 3300 and is positioned on theother side of the patient's head in use (e.g. across the other region)to assist in securing the patient interface 3000 on the patient's head.As shown, tube 3350 extends continuously from one side of cushionassembly 3150 to connection port 3600 and back to the other side ofcushion assembly 3150.

As depicted in FIG. 4B, left arm 3302 and right arm 3304 are connectedto each other in a continuous manner. That is, there are no specificconnection points between left arm 3302 and right arm 3304. Rather, thefluid connection extends seamlessly between the two arms. By formingtube 3350 continuously, the number of components of patient interface3000 may be reduced when compared to other forms of the presenttechnology.

In the exemplary form of the technology illustrated in FIGS. 4A-4D tube3350 curves around the upper part of the patient's head from the upperend of tube 3350 that includes connection port 3600 on top of the headto tab 3346, the point at which the rear headgear strap 3420 connects tothe tube 3350 substantially without any curvature in the coronal plane.In between tab 3346 at which the rear headgear strap 3420 connects tothe tubes 3350 and the lower ends of the tube 3350 where tube 3350connects with the cushion assembly 3150 in front of the patient'sairways under the nose, the tube 3350 curves forward or anterior betweenthe patient's ears and eyes and across the cheek region. The radius ofcurvature of this section of the tubes 3350 may be in the range 60-100mm, for example 70-90 mm, for example 80 mm. The lower end of the tubes3350 and the section of the tubes 3350 at which the rear headgear strap3420 connects to the tubes 3350 may subtend an angle in the range65-90°, for example 75-80°.

In the exemplary form of the technology illustrated in FIGS. 4A-4D, tube3350 extends substantially vertically in the superior direction (i.e.upwards) from proximate the otobasion superior to connection port 3600.That is, tube 3350 angles between 0 degrees and 15 degrees to thecoronal plane in an area between the otobasion superior and connectionport 3600. In other forms the angle may be greater depending on thepositioning by the patient. Additionally, tube 3350 is formed such tube3350 has a greater angle with respect to the sagittal plane from theotobasion superior to airway of the patient.

Further, as shown in FIG. 4B-4D, tube 3350 includes connection port3600. Connection port 3600 may be located partially within tube 3350.That is, a portion of connection port 3600 extends through outer layer3354 and between outer layer 3354 and inner layer 3352 of tube 3350. Inthis manner, connection port 3600 is sandwiched between the layers oftube 3350. Connection port 3600 may be configured to connect to othertubes such as air delivery tube 3348 of a therapy device that provideair flow from air circuit 4170. In some forms, air delivery tube 3348may form all of air circuit 4170 whereas in other forms air deliverytube 3348 forms a portion of air circuit 4170. Air delivery tube 3348may be formed of various materials, including textile materials,silicones, and other materials. By integrating connection port 3600within tube 3350, the quantity of seams or connection points along tube3350 may be diminished when compared to other forms of the presenttechnology. Further, by integrating connection port 3600 within tube3350 the use of additional connecting mechanisms such as adhesives,fasteners, or other additional mechanism features may be minimized orremoved. In other forms, connection port 3600 includes an inner portionand an outer portion. The inner portion may be located between innerlayer 3352 and outer layer 3354. The outer portion interacts with theinner portion such that outer layer 3354 is sandwiched between the innerportion and outer portion of connection port 3600.

In some forms textile is used to form various components of stabilizingstructure 3300. As depicted, tube 3350 is formed of a textile material.Some patients may find silicone tubes uncomfortable during use when thetubes rest against the face of the patient. Additionally, patients mayalso find silicone tubes uncomfortable even when a sleeve or sock oftextile material is placed over the silicone tube. The thickness andweight of the silicone tubes may cause a patient to stop use of thedevice. Further, when a patient lays on his or her head, the siliconetube may crease or bend such that the thickness of the tube is easilyfelt on the face of the patient, even when covered with a textilesleeve. A textile conduit or tube such as tube 3350 may increase comfortto some patients.

The textile material may be a flat planar sheet of material, or thetextile material may be formed with a three dimensional configurationsuch that the textile material has a positive or negative curvature. Asused in this specification “textile material,” or a “textile” may beused to describe any network of fibers. For example, a textile materialor textile may be woven, non-woven, knit, braided, or any other form ofa network of fibers. Different configurations of textile materials maybe utilized for different properties. For example, a woven configurationmay be utilized for particular strength laterally and longitudinally,whereas a knit structure may be utilized for flexibility andstretchability. Further, in some forms, the textile material may combinedifferent configurations to achieve particular properties. Additionally,the density of the material may be varied depending on the variousproperties desired. For example, if greater stretch is desired, a lessdense network of fibers may be utilized.

Further, a textile may be formed of various materials. A textile may beformed of natural or synthetic materials. Some examples include cotton,rayon, polyester, linen, silk, leather, polyurethane, monofilament ormultifilament materials may be used, or any combination of thematerials, in addition to other materials. A material may be selectedbased on the feel, texture, rigidity, flexibility, extensibility as wellas other factors. In addition, a textile may include both natural andsynthetic materials. Natural fibers or strands, such as cotton, may beutilized to provide a soft feel and comfortable fit to a patient. Asynthetic fiber may be used to provide rigidity or strength toparticular areas of the textile as well as for other properties.

In some forms of the present technology, different material may beutilized within the same textile material. Different materials may beutilized to provide particular properties to the textile component. Forexample, a stretchable fiber, strand, or yarn, may be included within atextile at a particular orientation to provide strength along alongitudinal or first direction. A second fiber that is substantiallyun-stretchable, inextensible, or stretch resistant may be includedwithin the textile along a lateral or second direction. In this mannerthe textile may be an anisotropic material that has different propertiesin various directions to provide support to the particular component.For example, a tube may be formed with a textile material. The textilematerial may be formed such that in a first direction the textilematerial is configured to expand or stretch when subjected to pressure.In a second direction that is different from the first direction thetextile material may be configured to resist stretching or deformingwhen subjected to pressure or force. For example, a tube may beconfigured such that the textile material expands radially whensubjected to air pressure. This stretching may allow for the tube toaccept or receive air and also allows the tub to be comfortable againsta patient. The tube, however, may have a particular longitudinalorientation along the face of a patient such that it is undesirable forthe tube to stretch in a longitudinal direction. By securing orrestricting stretch in the longitudinal direction, the positioning ofthe tube may be able to be maintained to allow a patient to receiveconsistent therapy.

In some forms, a textile tube may be formed of one or more sheets orlayers of textile material. In some forms a single sheet may be foldedor rolled and secured to itself along the lateral edges of the sheetsuch that a tube is formed with a single seam. In other forms more thanone sheet is utilized. For example, the textile tube may be formed witha first side that is configured to contact the patient. This may bereferred to as the inner layer. The textile conduit may also include asecond side that is attached to the inner layer, but faces away from thepatient that may be referred to as the outer layer. The inner layer andthe outer layer may each be secured to each other along the edges of theinner layer and the outer layer such that a channel or passageway isformed between the seams of the inner layer and the outer layer. Thatis, the space between the seams remains unattached.

As discussed in this detailed description, each of the inner layer andthe outer layer includes an interior surface and an exterior surface.The interior surface of the inner layer is the surface that faces theexterior layer. The interior surface of the exterior layer is thesurface that faces the interior layer. Likewise, the exterior surface ofthe outer layer faces away from the interior layer and the exteriorsurface of the inner layer faces away from the outer layer. Further, informs that include a single sheet, the interior surface is the surfaceof the sheet that faces inwards and towards itself.

In some forms, the sheet or sheets of the tube may include an airimpermeable layer or textile membrane. In some forms, the interiorsurface of both of the layers includes a membrane that is configured torestrict or restrain air from passing through the layer from theinterior surface to the exterior surface. The impermeable layer may be athin layer that is less than the thickness of the textile sheets of theinner layer or outer layer. In other forms, the impermeable layer may begreater than the thickness of the sheets of textiles of either of thelayers. The impermeable layer or textile membrane or film may becompletely impermeable to air transfer or may be formed to allow apredetermined rate or air transfer and particular pressures. In stillfurther forms, the membrane may be particularly designed to allow acertain amount or quantity of air or water vapor or moisture to passthrough the textile such that the tube 3350 is breathable allowingmoisture vapor to escape and/or be transmitted therethrough. By removingair through the membrane the need for a separate bleed-off valve forwaste air may be removed as the air may escape through the component,such as a tubing conduit or sealing structure itself. Further, in someforms, the permeability may be adjusted in particular areas. Forexample, the permeability may be altered in tube 3350 along a cheekregion. This area may become warm during use and causing discomfort tothe user. The permeability may be altered to allow some air to passthrough the tube 3350 to the patient's skin thereby causing a coolingeffect. The type of membrane and the permeability of the membrane may bealtered or tuned depending on the nature or use of the textile on whichthe membrane is located.

In some forms, the thickness of the textile membrane may be varied. Insome forms of the present technology, the textile membrane may be lessthan 5% of the thickness of the textile. In other forms, the thicknessof the textile membrane may be between 5% and 25% of the thickness ofthe textile. In still further forms, the thickness of the textilemembrane may be between 25% and 50% of the thickness of the textile.Additionally, the thickness of the textile membrane may be between 50%and 100% or greater of the thickness of the textile. Varying thethickness of the textile membrane affects the rigidity andstretchability of the textile. For example, a textile that includes atextile membrane that is 1% of the thickness of the textile may be lessrigid and more stretchable than a textile that includes a textilemembrane that is greater than 50% of the thickness of the textile. Insome forms, a thicker textile membrane may be utilized to provideadditional strength in particular areas of a conduit or sealinginterface. That is, the thickness of the textile membrane may beincreased in high stress areas or areas more likely to experiencekinking or folding during use.

The membrane may be formed of thermoplastic or thermoset materials suchthat when exposed to a particular temperature the membrane material maybe able to be molded or shaped into a particular form and then cures orsolidifies or sets upon cooling. In some forms the membrane may beformed of silicone or polyurethane.

Further, in some forms, the membrane material may assist in joining theseams of the layers together. For example, a thermoset or thermoplasticmaterial when exposed to a particular heat may cross-link such as inthermoset materials or may melt such as in thermoplastic materials. Whensolidified, the materials may be joined together. For example, themembrane along interior surface 3356 of outer layer 3354 and themembrane along interior surface 3358 of inner layer 3352 may besubjected to heat along the edges of outer layer 3354 and inner layer3352 to form a seam between the two layers.

The inner layer may be attached to the opposite outer layer along afirst and second seam. Once the layers are attached to one another, atube or conduit may be formed between the two layers. By securing thelayers along the edges, a central chamber is formed that allows for theflow of air or other gas or liquid medium when secured with air circuit4170.

Tube 3350 as shown in FIG. 4B is formed using a textile that includes amembrane. Tube 3350 includes inner layer 3352 and opposite outer layer3354. Both inner layer 3352 and outer layer 3354 include an impermeablemembrane along the interior surface of the layers. Although describedand depicted as including only an interior surface coated with animpermeable layer, in some forms, both the interior surface and exteriorsurface of the layers of tube 3350 may include an impermeable membrane.In some forms, the impermeable membrane, however, may be oriented awayfrom a patients face. By orienting tube 3350 in such a manner, the softfeeling of fabric may be pressed against a patient while the impermeablemembrane layer is spaced from the patient. This allows for a singlepiece of material to be formed that has different properties dependingon the side of the material that is utilized. This may reduce productioncosts as well as the time necessary or required to form the component.

5.3.3.1.1.1 Shape and Composition of Tube

Referring to FIG. 4F a cross section of tube 3350 is depicted. In someforms, the inner layer 3352 and outer layer 3354 may be formed ofmultiple layers of textile material and/or membrane material. By varyingthe thickness and composition of the layers of tube 3350, differentcharacteristics may be achieved. As shown in FIG. 4F, and in particularFIG. 4F-1 inner layer 3352 comprises a textile sheet 3360 along withtextile membrane 3362. Textile sheet 3360 may be formed of felt, spacerfabric, foam, woven, knit, or non-woven material or other network offibers. As shown, textile sheet 3360 is a felt-type textile. In thismanner, exterior surface 3374 of inner layer 3352 may have a soft feelagainst the face of a patient. Outer layer 3354 is composed of multiplesheets of textile. Outer layer 3354 includes tube sheet 3364 and outercovering 3366. In some forms, both sides of tube sheet 3364 may becovered with a textile membrane. As shown in FIG. 4F-2, tube sheet 3364includes textile membrane 3368 exposed to the chamber of tube 3350 andtextile membrane 3370 along an opposite surface of tube sheet 3364.Textile membrane 3368 may assist in providing a seal between inner layer3352 and outer layer 3354 as well as forming an air tight tube. Textilemembrane 3370 may assist in joining tube sheet 3364 to outer covering3366. In other forms, tube sheet 3364 may directly bond or join to outercovering 3366. In other forms, outer layer 3354 includes a shape holdingmaterial or material that is able to be thermoformed such as a foamlayer located between tube sheet 3364 and outer covering 3366. In otherforms, tube sheet 3364 may be able to be thermoformed. As discussed indetail later in this detailed description, the shape holding materialmay be utilized to provide a predetermined shape for tube 3350.

The configuration, orientation, and composition of the sheets of innerlayer 3352 and outer layer 3354 may assist in providing a supportstructure to tube 3350 to prevent occlusion during use. As shown in FIG.4F, the cross-section of tube 3350 is substantially D-shaped such thatan air passage 3372 is formed between inner layer 3352 and outer layer3354. Inner layer 3352 is substantially planar such that inner layer3352 has zero curvature. Outer layer 3354 curves away from inner layer3352 such that interior surface 3356 of outer layer 3354 has a positivecurvature between the joints. As shown, the curvature of the interiorsurface 3356 changes between the joints of tube 3350. That is, thecurvature may be negative adjacent to where inner layer 3352 and outerlayer 3354 are joined together. It should be recognized however, thatthe overall curvature when taken from the central point between thejoined edges of tube 3350 is positive. In other words, the outer layer3354 has a non-planar configuration forming an arc-shaped portion, incross-section, between the joined edges. That is, interior surface 3356of outer layer 3354 may have a concave shape and an exterior surface3376 of outer layer may have a convex shape. The curvature of outerlayer 3354 may be fixed such that when outer layer 3354 is not subjectedto force such as by weight of an external force or air pressure,interior surface 3356 of outer layer 3354 has a substantially positivecurvature. Thus, inner layer 3352 and outer layer 3354 are asymmetricalwhich is in contrast to some conventional conduit portions which haveidentical or symmetrical shapes.

Further, the interior surfaces of inner layer 3352 and outer layer 3354may be D-shaped in cross-section. That is, the interior surface maybound a D-shape air passage 3372. In some forms, therefore, the interiorsurfaces of inner layer 3352 and outer layer 3354 may form a D-shape incross-section, and the exterior surfaces of inner layer 3352 and outerlayer 3354 may also form a D-shape in cross-section.

In another manner, outer layer 3354 may curve away from inner layer3352. As shown in FIG. 4F, outer layer 3354 and inner layer 3352 areattached to each other along longitudinal edges such that the edges ofinner layer 3352 and outer layer 3354 are flush with one another.Between these attachment points, adhering zones or joints, outer layer3354 is curved away from inner layer 3352. That is, between joints 3312(see FIG. 4H), interior surface 3356 of outer layer 3354 is positionaway from interior surface 3358 of inner layer 3352. In some forms,outer layer 3354 may be pre-formed such that in an unpressurized orsupported state, outer layer 3354 is pre-positioned and pre-formed toextend away from inner layer 3352 between the opposing joints 3312. Thatis, outer layer 3354 may support its own weight such that when notsupported by pressurized air or other support mechanism, outer layer3354 remains spaced from inner layer 3352 between joints 3312.

The generally D-shaped cross-section may vary along its length, e.g.,tall, thin D-shaped cross-section near the patient's nose and wide,shallow D-shaped cross-section along cheek and near the top of thepatient's head. For example, FIGS. 4I-4K illustrate variouscross-sections of tube 3350 along its length according to one form oftube 3350. As illustrated, the D-shape of the cross-section varies alongits length. Specifically, each cross-section has a width w and a heighth, and the width and height of the various cross-sections varies alongthe length of the tube, e.g., a relatively long width and short heightat the manifold end compared to a relatively short width and tall heightat the interfacing structure end. In some forms, the D-shapedcross-section of the tube 3350 may be asymmetrical along an entirelength of the tube or at least along a portion or portions of the tube.Also, all of the cross-sections have a very similar or common hydraulicdiameter, e.g., about 10-15 mm or about 13 mm. Further, the width andheight may refer to the chamber size rather than the entire size of thecross-section including external seam areas.

Additionally, tube 3350 may provide flatter regions in certain areas,e.g., where the patient rests on the tube during sleep. In this way, thetubes can be said to be an organic extension of the patient's facialcontours. The shape may be configured based on aesthetic and/orimpedance requirements. In addition, the shape may be configured toprovide low profile, comfort, and/or stabilization. However, tube 3350may have other suitable cross-sectional shapes, e.g., trapezoidal,semi-circular, cylindrical, oval, elliptical, flatter section, etc.Also, the tubes may have a flat configuration with anti-crush ribs. Thisarrangement is disclosed in U.S. Pat. No. 10/385,701, the entirety ofwhich is incorporated herein by reference.

Further, tube 3350 as depicted in FIGS. 4L-1 to 4L-4 may be soft so thattube 3350 is readily deformable under finger pressure. That is, tube3350 may not be formed of a rigid structure that is unable to deform.Rather, tube 3350 is formed such that tube 3350 is able to deform whensubjected to finger pressure. Tube 3350, however, is also able tomaintain its shape when under no force from air pressure or otherwise.

Additionally, outer layer 3354 may be a resilient structure. Outer layer3354 is able to deform when subjected to pressure or force during normaluse to accommodate a patient's movement during sleep and use. Forexample, tube 3350 may collapse such that outer layer 3354 is pressedagainst inner layer 3352 not only at the sealed edges, but also betweenthe sealed edges. When force is removed from outer layer 3354, however,outer layer 3354 may return to its pre-determined shape that includes aninterior surface of positive curvature. That is, outer layer 3354 is nota floppy structure because outer layer 3354 is able to support its ownweight without changing in shape such as by bending or twisting. Outerlayer 3354 may have a hardness of between Shore OO10 to Shore OO30. Inother forms, outer layer 3354 may be harder such that outer layer 3354is configured to resist larger forces.

Outer layer 3354 may comprise materials that resist plastic deformation.For example, outer layer 3354 may be bent or folded such that portionsof exterior surface 3376 may abut itself when subjected to force. Oncethe force is released, however, the outer layer 3354 returns to itspre-force shape. Rather than plastically deforming, or failing, outerlayer 3354 elastically deforms and returns to its pre-determined shape.Further, a majority of tube 3350 may be able to be bent, folded, ortwisted in a similar manner. That is, tube 3350 may be formed ofmaterials that when folded onto themselves do not plastically deform.

In contrast, inner layer 3352 may be a floppy component. Inner layer3352 may be attached and secured to the edges of outer layer 3354 suchthat inner layer 3352 is a substantially planar layer. The shape ofinner layer 3352 may be influenced by the shape of outer layer 3354. Asshown, inner layer 3352 may be planar because of the force exerted toinner layer 3352 through the seams of tube 3350. Because outer layer3354 resists deformation, outer layer 3354 is able to maintain thetautness of inner layer 3352 so that inner layer 3352 is planar. Inother forms, inner layer 3352 may be cut such that inner layer 3352 iswider than outer layer 3354, however inner layer 3352 is still connectedto outer layer 3354 along the edges of tube 3350. In such forms, theunsecured portions of inner layer 3352 may be able to move inwardstoward outer layer 3354.

In some forms, inner layer 3352 may be floppy in some areas and rigid inothers. For example, in some forms a rigidizer may be utilized at withinarm support 3314 thereby imparting a rigidity to inner layer 3352 suchthat inner layer 3352 is not floppy in the particular area. In someforms, between the seals of tube 3350 however, inner layer 3352 mayremain floppy. That is, no additional rigidizer is utilized between theseals or joints of tube 3350. A rigidizer may have a shore hardness ofbetween Shore A30 and Shore A90 or higher.

In other forms, inner layer 3352 may be at least semi-resilient. Thatis, although inner layer 3352 may not be able to support its own weight,inner layer 3352, with assistance from outer layer 3354 may be able tosupport some of its own weight such that inner layer 3352 resides insubstantially the same location when not subjected to additional forcesuch as air pressure or other external forces.

Inner layer 3352 as depicted is relatively flat and adapted to sitsubstantially flush against the patient's face in use. Inner layer 3352may have a tapered configuration from an inner edge to an outer edge toprovide a comfortable fit for a wide range of patients. Inner layer 3352provides a relatively large surface area which results in a more evenload distribution. This arrangement is less likely to create pressurepoints in use. Also, internal layer 3352 may have grip-like material tohelp stabilize the patient interface on the patient's face.

In some forms, outer layer 3354 may be more resilient than inner layer3352. That is, outer layer 3354 may be more resistant to deformationthan inner layer 3352. Further, outer layer 3354 may return readily to apre-determined shape to a greater degree than inner layer 3352. Further,in some forms, outer layer 3354 may be stiffer or more rigid that innerlayer 3352. As shown in FIGS. 4F to 4F-2, outer layer 3354 may includemore layers than inner layer 3352, and the outer layer 3354 may have agreater thickness than inner layer 3352. Such configuration of the outerlayer 3354 and inner layer 3352 may assist in providing a relativelystiffer or more rigid outer layer 3354. The increased stiffness,rigidity, and/or resiliency may assist in maintaining an open passagewaythrough which air can travel. Further, in some forms, outer layer 3354may include harder materials than inner layer 3352. This composition ofmaterials may assist in providing a stiffer or more rigid outer layer3354.

Outer layer 3354 has a smooth contour that blends with the patient'sface. That is, outer layer 3354 has a profile or organic form with edgesthat blend into the patient's face, e.g., in a tangential manner, toprevent any edges from catching on bedclothes, pillows, etc., duringsleep (e.g., when the patient rolls over). As illustrated, tube 3350 hasa non-cylindrical cross sectional shape which provides a blendingcontour to blend with the patient's face (See FIGS. 4A-4D). The blendingcontour is smooth, streamlined, sleek, and blends or tapers tube 3350with or into the contours of the patient's head, e.g., anatomicallycoherent, less obtrusive and more aesthetically appealing. In addition,the blending contour has no sharp edges that could cause discomfort,e.g., skin irritations or abrasions.

In some forms, outer layer 3354 may be thermoformed such that materialswithin outer layer 3354 assume the shape of a mold or mandrel. Whencured or cooled, the thermoformed material assumes the shape as shown inFIG. 4F. In some forms, an additional layer may be located between outercovering 3366 and tube sheet 3364. In some forms the additional materialmay be a foam or other thermoset material. In other forms, tube sheet3364 or outer covering 3366 or both may be formed of a foam orthermosetting material. In still other forms, thermoplastic material maybe utilized. In still other forms, any other shape holding material maybe utilized. As shown, the cross-sectional shape of tube 3350 may bemaintained without additional rigidizers or components beyond the sheetsof outer layer 3354 and inner layer 3352. Further, the thickness of theinner layer 3352 may be substantially the same along the width of innerlayer 3352. Further, outer layer 3354 may also be substantially the samethickness along the width of outer layer 3354. When thermoformed, outerlayer 3354 may be able to maintain its pre-determined shape withoutassistance from inner layer 3352. That is, outer layer 3354 is able tomaintain its predetermined shape without tension, force, or support,from inner layer 3352.

Turning to FIG. 4R, patient interface 6000 may include a vent formed inthe tube 3350 (e.g., in the outer layer 3354) to expel exhaust gases toatmosphere. In the illustrated example, the vent 6100 is formed near thecushion assembly 3150. Additionally, air delivery tube 6348 may have atextile construction. For example, air delivery tube 6348 may have aconstruction similar or identical to any of the tube embodimentsdisclosed herein.

Referring to FIG. 4S, patient interface 7000 includes positioning andstabilizing structure 7300. Positioning and stabilizing structure 7300includes tube 7350 having left arm 7302 and right arm 7304. The left andright arms may be separate structures having connectors at upper andlower ends thereof so that the arms are individually removablyconnectable to both the cushion assembly 3150 and the hub 7200. Forexample, at the upper and lower ends of each of the left and right arms7302, 7304, an upper connector 7312 and a lower connector 7314 arerespectively provided, as shown in FIGS. 4T and 4U. The upper connectors7312 are configured to removably connect to the hub, whereas the lowerconnectors 7314 are configured to removably connect to the cushionassembly 3150.

Referring to FIGS. 4T and 4U, each of the upper and lower connectors7312, 7314 in these examples may include a connector body 7303, a slot7309, a chamfered edge 7308, and a notch 7306 that may be removablyconnected to clips in the cushion assembly 3150 and hub 7200 with asnap-fit. In an alternative example, the connectors 7312, 7314 may beprovided in the cushion assembly 3150 and/or hub 7200 and the receivingportions may be provided on the left and right arms 7302, 7304.

As shown in FIG. 4S, an elbow 7220 may be swivelably connected to thehub 7200 and include a swivel connector at an opposing end thereof forconnection to an air delivery supply tube.

Turning to FIG. 4V, an illustration of a cross-section of tube 7350 isshown. Similar to outer layer 3354, outer layer 7354 may be structuredso that it can support its own weight. As can be seen, outer layer 7354includes an outer covering 7402 forming an exterior surface of the outerlayer that is positioned away from the patient's face in use. An outercushioning layer 7406 (e.g., foam) is positioned between the outercovering 7402 and a textile member 7410 that forms an air impermeablesurface of the air passageway. The outer cushioning layer 7406 may bethermoformed to hold its shape. Adhesive layers 7404, 7408 may berespectively provided between the outer covering 7402 and the outercushioning layer 7406 and between the outer cushioning layer 7406 andthe textile membrane 7410. In an alternative example shown in FIG. 4W,the outer cushioning layer 7406 and adhesive layer 7408 may be removed.

Turning back to FIG. 4V, inner layer 7352 includes a textile sheet 7222configured to engage the patient's face in use. An inner cushioninglayer 7426 (e.g., foam) is positioned between the textile sheet 7222 anda textile member 7230 that forms an air impermeable surface of the airpassageway. Adhesive layers 7224, 7228 may be respectively providedbetween the textile sheet 7222 and the inner cushioning layer 7226 andbetween the inner cushioning layer 7226 and the textile membrane 7230.

Turning to FIG. 4X, patient interface 8000 includes positioning andstabilizing structure 8300 having tube 8350. Each of left arm 8302 andright arm 8304 may have a lower portion 8362 and an upper portion 8364which may have different rigidities. For example, lower portion 8362 maybe more rigid than upper portion 8364, or vice versa. This may beaccomplished, for example, by constructing the inner layer 3352 of lowerportion 8362 to have a different rigidity than the inner layer 3352 ofupper portion 8364 and/or constructing the outer layer 3354 of lowerportion 8362 to have a different rigidity than the outer layer 3354 ofupper portion 8364. It is noted that instead of only a lower portion andan upper portion, each of the left arm and right arm may have threesections with different properties (e.g., rigidity).

In the illustrated example, the inner layer 3352 and the outer layer3354 of lower portion 8362 are respectively more rigid than the innerlayer 3352 and the outer layer 3354 of upper portion 8364. As such, theupper portion 8364 is more flexible and better able to conform to thecurvature along the side of the patient's face up to the top of thepatient's head. Tab 3346 may be provided on lower portion 8362 which mayallow for better connection to the strap 3420 since the increasedrigidity of the lower portion aids in resisting torsion and maintainingthe desired application of vector forces. Alternatively, tab 3346 may beprovided on the upper portion 8364 or bridging the upper portion 8364and lower portion 8362.

In some forms, the cross-sectional shape of the tube may be particularlyformed. For example, in some forms, the tube may be pre-formed to have aflat or planar contacting surface, and a convex outer layer. The shapeof the conduit may be formed in particular shapes to provide aparticular feel as well as to regulate the amount or quantity of oxygenor air that is forced through tube 3350 to the patient. That is, theconduit may be formed to limit how much the conduit stretches or expandswhen subjected to an air or oxygen source. Further, the cross-sectionalshape of tube 3350 may change along the length of tube 3350. Forexample, the cross-sectional shape tube 3350 may be different adjacentto connection port 3600 as compared to adjacent cushion assembly 3150.The cross-sectional shape as well as volume encompassed by theparticular shape may be changed or altered depending on how patientinterface 3000 is configured to interact with the patient. For example,an end of left arm 3302 may have a smaller cross section than the pointat which left arm 3302 connects with connection port 3600. Because theend of left arm 3302 is more likely to be associated with a sensitiveportion of the face of a patient, limiting the cross-sectional size ofthe end of left arm 3302 may increase comfort to the patient whencompared to other forms of the present technology.

Further, changing the width of the inner layer or the outer layer maypermit the size of the chamber to be altered or varied. For example, theportion of inner layer 3352 that forms a portion of air passage 3372 mayhave a width W1 at a first location of left arm 3302 as shown in FIGS.4C and 4G. When joined together, inner layer 3352 and outer layer 3354form a cavity or chamber associated with air passage 3372 with across-sectional area and also a volume V1. As shown in FIG. 4H innerlayer 3352 and outer layer 3354 may also have a width W2 that is spacedalong left arm 3302 from width W1. Width W2 may be greater than widthW1. Additionally, as shown, the cavity formed in the area of W2 isvolume V2 that is larger than volume V1. Therefore, when breathable airis passed through the area of width W2, the cross-section area of tube3350 at a location with width W2 is greater than the cross sectionalarea of tube 3350 at a location with width W1. Further, at a locationwith second width W2 the volume of the chamber may be greater than thevolume at the first width.

The width may be varied to provide various properties or functions. Insome forms, changing the volume of air or oxygen within a particularpoint may be used to alter the flow speed through various portions ofthe textile conduit. For example, if a textile conduit has a largecross-sectional area at a first location, breathable air that passesthrough the textile conduit may flow at a first speed. If the textileconduit also has a smaller cross-sectional area at a second location,the breathable air that passes through the textile conduit at the secondlocation may flow at a second speed is greater than the first speed.Therefore, the conduit volume size may be changed to speed up or slowdown the speed of the air through the conduit.

In some forms, the chamber size of a textile conduit may be changed byvarying the shape of the textile layers and/or varying the width of thejoining or joint of the textile tube or conduit. The joint refers to thearea of one layer of the tube that is joined to the other layer of thetube, or in some forms where one layer attaches to itself when a tube isformed of a single layer. For example, as shown in FIG. 4G the joint3312 is where a layer such as inner layer 3352 is joined to lower layer3354.

Varying the width of the joint 3312 varies the size of the chamberformed within the textile conduit. For example, a wider joint reducesthe chamber volume compared to a narrower joint. The width of the jointmay be different on either side of the textile conduit. Further, thewidth of the joint may also vary along the length of the textileconduit.

Varying the width of the joint 3312 may permit the rigidity of thetextile conduit to be varied along the length. For example, in alocation that may be subjected to higher stress or greater likelihood ofbending, the width of the joint may be greater than in areas that do nothave the same likelihood of bending. The width of joint 3312 may bedependent on how wide the welding mechanism or cutting mechanism is thatis used to form tube 3350. In other forms, a separate heating mechanismmay also be utilized to join the layers together. In such circumstancesthe heating mechanism may be moved about to create a wider or narrowerjoint 3312. Although shown along an outside portion of tube 3350, insome forms tube 3350 may be flipped inside out such that the joint islocated within the chamber of tube 3350.

In some forms, the location of the joint 3312 around the D-shapedcross-section of the tube 3350 may be altered to adjust flexibility andrigidity of the tube along the length of the tube.

In some forms, the joints may be formed using various techniques thatimpart particular properties to the joint. For example, in some forms,the joints are formed using ultrasonic welding, radio frequency welding,as well as cut and weld techniques. Heat may be applied in particularareas that activates a thermoset or thermoplastic material used in tube3350. This heat may not only be used to join the layers together, butmay also be used to thermoform the layers, such as outer layer 3354.Further, in some forms stitching or an adhesive such as a glue may beutilized to join the layers together. In some forms, stitching is notused. In still further forms, material beyond what is located within thelayers is not utilized to join the inner and outer layers of tube 3350.For example, in some forms the inner and outer layers may be formed suchthat no additional material such as glue or stitching, is necessary tojoin the inner and outer layers together.

In some forms, a sleeve (e.g., constructed of textile) may cover thetube 3350 to replicate the impression of bedclothes.

5.3.3.1.1.2 Shape of Patient Interface

Tube 3350 also may have various curvatures along its length tocorrespond with the shape of the face of the patient. As discussedpreviously, the cross-section of tube 3350 may have a particular shape.The shape of tube 3350 may vary along its length (rather than just itswidth as depicted in FIG. 4F). For example, interior surface 3358 ofinner layer 3352 may have generally positive curvature along the lengthof inner layer 3352. This curvature may be included into tube 3350 tocorrespond to the generally negative curvature of the face of a patientalong the areas in which tube 3350 contacts the head of the patient. Itis recognized that the curvature of the face of a patient is complex andvaried, however, overall, at the points at which tube 3350 contacts thehead of the patient the head is generally negatively curved. Further,this curvature may be accomplished even when headgear 3300 is not wornby a user. That is, the curvature of the length of tube 3350 maycorrespond to a pre-determined, non-planar configuration.

Referring to FIGS. 4L-1 to 4L-4, tube 3350 is shown in isolation. Asshown, tube 3350 is bent or formed along three dimensions such thatinner layer 3352 and outer layer 3354 are located about various planes.For example, outermost portion 3378 of outer layer 3354 adjacent toconnection port 3600 extends along the XY plane. In contrast, outermostportion 3380 of outer layer 3354 of right arm 3304 is located along theYZ plane. In addition, in some forms, tube 3350 may include additionalbends such that right arm 3304 is rotated along the Z axis so that aportion of outermost portion 3380 extends along the XZ plane. In thismanner, tube 3350 may have a three dimensional pre-determined shape.

Particular views of portions of tube 3350 are depicted in FIGS. 4L-2 to4L-4. Specifically, FIG. 4L-2 depicts a side view of a portion of tube3350. FIG. 4L-3 is a front view of a portion of tube 3350. FIG. 4L-4 isa top view of a portion of tube 3350.

Tube 3350 may be stiffer in particular regions based on geometry of tube3350. As shown in FIG. 4L-1 bending or twisting tube 3350 about variousaxes may require differing levels of force. That is, tube 3350 mayresist deformation or bending along a plane or axis to a greater extentin a first area than to a second area. For example, twisting or bendingtube 3350 along the XY plane may require different levels of force atfirst area 3308 adjacent to connection port 3600 compared to second area3310 of right arm 3304. By arranging tube 3350 in particular directions,the strength of the cross-sectional shape of tube 3350 may be utilizedto resist bending in particular directions to assist in providing asecure patient interface 3000.

Additionally, tube 3350 as depicted in FIG. 4L-1 may be bent or orientedto varying degrees. For example, left arm 3302 and right arm 3304 may beoriented closer than depicted to each other. That is, the spacingbetween left arm 3302 and right arm 3304 along the X axis may besmaller. The spacing between the arms may be modified during themanufacturing of tube 3350 depending on the particular shape desired.Further, in some forms the shape of tube 3350 may be configured to alignor conform to the face of a patient. Tube 3350 may have a complimentaryshape to that of the patient. For example, a portion of the patient'sface has a negative curvature. The exterior surface 3374 of inner layer3352 may be configured to have an opposite positive curvature such thatinner layer 3352 lies flush against the face of the user. Additionally,in other areas the patient's face has a positive curvature. The exteriorsurface 3374 of inner layer 3352 may be configured to have an oppositenegative curvature such that that inner layer 3352 lies against the faceof the user. Tube 3350 may be formed with an inward bend at the arms,such that tube 3350 provides compression to the face of the user. Thatis, in some forms, left arm 3302 and right arm 3304 may be oriented atan angle with respect to the planes. Left arm 3302 may be located withina plane that if extended intersects the plane on which right arm 3304 islocated. This orientation may provide compression against the head ofthe user to assist in providing comfortable, and form-fitting placement.

In some forms, the left arm 3302 and right arm 3304 may haveconcertina-shaped portions to increase flexibility of the left and rightarms allowing the arms to bend to conform to the patient's face.

In some forms, the shape of the tubes may be particularly formed. Thetop view shape of the conduit may be varied. In contrast to siliconetubes, the shape of a textile tube may be cut and formed to produce aparticular shape rather than being formed entirely by molding such asinjecting molding. This ability to determine the particular shapewithout complicated molds may permit the cost of manufacturing todecrease when compared to other forms.

In some forms, the layers may be knit in a particular manner such thatthe layer is knit to shape. In other forms, a woven, non-woven or othertextile of a network of fibers may be cut to shape. In some forms, anL-shaped conduit may be formed. In other forms, for example as shown inFIG. 4E, a U-shaped tube 3350 may be formed. By forming an air deliverysystem from a textile material, various other shapes and configurationsmay be formed. Further, working with flat or planar sheets may assist inmanufacturing and assembly. Because the material may be worked within2-dimensional space the complexity of the joints, connections, or bendsis reduced. Although shown in two dimensions in FIG. 4E for ease ofviewing, in other forms, such as shown in FIGS. 4A-4D, tube 3350 mayalso be bent or twisted during manufacturing such that tube 3350 has apre-determined 3-dimensional shape.

In some forms, multiple layers may be combined to form a tube. Incontrast to other forms, by forming a tube with multiple separatesheets, intricate designs and specific shapes may easily be formed. Forexample, rather than forming a tube in a 3-dimensional shape, the shapemay simply be cut out of a two dimensional layer. The layer then may besubjected to additional processing such that a 3-dimensional shape isformed. By initially forming or planning the forming of the shape in2-dimensions, processing may be simpler, less time consuming, and costeffective than in other forms.

Patient interface 3000, in addition to maintaining a shape withoutpressure or force, may be configured to spring to shape. Patientinterface 3000 may be located within packaging prior to a patientopening and using patient interface 3000. Some patient interfaces thatexist today are difficult to orient to don on a patient's head. Thestraps of some interfaces entangle with each other such that it is notclear how to correctly wear the patient interface. Patient interface3000, however, is formed such that when removed from packaging, orluggage, or any confined space, patient interface 3000 will spring toits predetermined shape. That is, without additional effort from a user,patient interface 3000 will orient the arms of patient interface 3000such that how patient interface 3000 is worn is apparent to a patientwithout additional untangling or arranging of the components of patientinterface 3000. This configuration may allow the patient to easilyutilize patient interface 3000.

5.3.3.1.1.3 Structural Support

In some forms, a joint may be utilized as both a seal for tube 3350 aswell as a rigidizer or support structure for tube 3350. Arm support 3314is a wider joint that may be utilized to particularly direct forcevectors and to provide a seal between seal-forming structure 3100 andthe airways of a patient. Arm support 3314 may resist bending such thatsufficient force is provided both rearwardly and upwardly to cushionassembly 3150 through tube 3350 to provide a seal between seal-formingstructure 3100 and the airways of a patient. Referring to FIGS. 4A-4D,stabilizing structure 3300 includes arm support 3314. Arm support 3314,as shown, extends along a portion of left arm 3302. An arm support mayalso be included along a portion of right arm 3304. Arm support 3314resists bending of left arm 3302 such that when patient interface 3000is worm by a patient seal forming structure 3100 maintains the correctpositioning with regard to the face or nose of a user. For example, whenworn, headgear 3300 may tend to straighten out between the otobasionsuperior of the patient and the airway of a patient. That is, headgear3300 may tend to straighten out where tube 3350 bends toward cushionassembly 3150. Arm support 3314 resists the rotation of left arm 3302about the X axis. Arm support 3314 as depicted is formed of inner layer3352 and outer layer 3354. That is, no additional material or componentsare utilized in arm support 3314 such that arm support 3314 is onlyformed of the materials and layers used to form tube 3350. In thismanner, stabilizing structure 3300 may be formed in an efficient mannerthat does not require additional components. Further, separaterigidizers beyond inner layer 3352 and outer layer 3354 may be includedin various portions of tube 3350, such as within arm support 3314 oralong the outer surfaces of arm support 3314.In other forms of thepresent technology, separate rigidizers are used to provide rigidity totube 3350. A rigidizing element in accordance with one form of thepresent technology is preferably thin and conforming when a patient liesupon it, yet has sufficient stiffness to resist out-of-plane bending.That is, the rigidizing element is structured to allow bending in someplanes and resist bending in other planes, e.g., allow bending towardsand away from the patient's face. The rigidizing element also makes tube3350 inextensible in areas in which a rigidizing element is utilized ornot stretchy so that tube 3350 is strong in tension and maintains itssize. The rigidizing element may be located within the airflow path oftube 3350 or may be located outside of tube 3350.

Further, a rigidizer may correspond to a component that has a greaterhardness and/or stiffness than surrounding material. Additionally, therigidizer is utilized to resist finger deformation. Further, a rigidizermay refer to a component in addition to the layers that form inner layer3352 and outer layer 3354. For example, particular areas of tube 3350may include additional components beyond the materials used to forminner layer 3352 and outer layer 3354. In some forms, connection port3600 (see FIGS. 4M and 4N) may be considered a rigidizer. Connectionport 3600 may be formed of a material that is harder than thesurrounding material, and connection portion 3600 may resist fingerdeformation. In other forms, a rigidizer may refer to a material otherthan inner layer 3352 and outer layer 3354 that is permanently attachedto either inner layer 3352 or outer layer 3354. Further, a rigidizer mayincrease the rigidity of the layers with which the rigidizer is incontact when compared to the material layers without the rigidizer.

In one form, the rigidizing element may provide structural integrity orself-holding form to the patient interface so that the patient interfacecan hold its shape and not fall into a heap, e.g., shape memory, whetherthe patient interface is on or off the patient's head. The shape holdingarrangement maintains the tubes in a desired position and may facilitatedonning of the patient interface in use.

In some forms, a rigidizing element may be utilized in particularlocations. For example, a rigidizing element may be utilized between thelayers of stabilizing structure 3300. For example, a rigidizing elementmay be located between inner layer 3352 and outer layer 3354. In otherforms a rigidizing element may be located between the various sheetsthat form inner layer 3352 and outer layer 3354. In other forms arigidizing element may be located along an inner or outer surface ofstabilizing structure 3300. In further forms, a rigidizing element maybe located at areas of high stress such as when head strap 3420interacts with tube 3350. A rigidizing element may be utilized toproviding rigidity to the overall shape of patient interface 3000, aswell as providing support for the cross-section of tube 3350, therebyresisting the collapse of tube 3350.

In some forms, a rigidizing element may be located along an outersurface of headgear 3300. For example, a rigidizing element may belocated along exterior surface 3376 of outer layer 3354 at the locationof arm support 3314. In some forms, between connection port 3600 andassembly connection ports 3154 and 3155 there is no rigidizer within thechamber of tube 3350. In other forms, between connection port 3600 andassembly connection ports 3154 and 3155 there is no rigidizer betweenthe joints of inner layer 3352 and outer layer 3354. In still furtherforms, there is no rigidizer that contacts inner layer 3352 betweenconnection port 3600 and assembly connection ports 3154 and 3155.

In other forms, the structure and orientation of the inner layer 3352may allow bending in some directions and have sufficient stiffness toresist bending in other directions. That is, the inner layer 3352 may bestructured to allow bending in some planes and resist bending in otherplanes, e.g., allow bending towards and away from the patient's face toconform to the patient's head and resist bending along the plane inwhich the inner layer 3352 extends. Thus, a first plane in which theinner layer 3352 is configured to bend may be perpendicular to a secondplane in which the inner layer 3352 resists bending. The outer layer3354 also may allow bending and resist bending similarly to the innerlayer 3352.

As mentioned above, the joint 3312 may form a rigidizer. The joint 3312may be configured such that the tube 3350 allows bending in some planesand resists bending in other planes, e.g., allows bending in a firstplane towards and away from the patient's face to conform to thepatient's head and resists bending along a second plane in which theinner layer 3352 extends. Further, the joint 3312 may be configured tobe substantially rigid so as to resist bending in the first and/orsecond plane.

In other forms, the size of the conduit may contribute to the resistanceto bending. For example, in some forms the conduit may have a smallercross-section in a first area. In the first area, for example an areathat has a width W1, there is a greater density of material whencompared to the volume or space that the first area can contain. Byincreasing the density of material at a given location, the strength orrigidity or resistance to bending or deformation normal to outer layer3354 in a particular area may be increased when compared to other areas.Particular areas that may be subjected to increased forces such asbending or kinking may be particularly shaped such that particularmaterial is utilized to resist bending or kinking. For example, asshown, tube 3350 is narrower at an end point 3306. End point 3306 may beconnected to cushion assembly 3150. A mask area may be more likely to beexposed to bending and kinks. Therefore, by changing the density of thematerial at the mask connection location, the likelihood of kinks andbends within the tube 3350 may be reduced.

5.3.3.1.1.4 Tube Layer Properties

In some forms, inner layer 3352 and outer layer 3354 are formed ofdifferent materials. In some forms, inner layer 3352 may be formed of asofter or gentler textile material than outer layer 3354. Because innerlayer 3352 is exposed to the skin of the patient, the material of innerlayer 3352 may be particularly formed to feel comfortable along the skinof a patient. Outer layer 3354 may be a different material than theinner layer. Outer layer 3354 may be more likely to be caught by anabrasive material or rub against an object. Therefore, in some formsouter layer 3354 is formed of a durable material that may not be as softas the inner layer. Further, exterior surface 3376 of outer layer 3354as well as exterior surface 3374 of inner layer 3352 may have differentsurface properties than the interior surfaces of the respective layers.Additionally, exterior surface 3374 may have a higher coefficient offriction than the exterior surface 3376 of outer layer 3354 to maintainthe location of the positioning and stabilizing structure of thepatient's face.

In some forms, particular surfaces may be layered with a membrane. Forexample, in some forms, only the interior of the conduit or sealingstructure includes a membrane. Therefore, the exterior surface and theinterior surface may have different properties. The exterior surface maybe softer and breathable and may be formed of cotton. This surface maybe more pleasing or comfortable to a patient than a silicone orpolyurethane surface. The interior surface, however, may be layered orcoated with a membrane. Therefore, the membrane surface may be spacedfrom or isolated from the skin of the patient. By having differentmaterial properties on either the interior or exterior surface of atextile conduit, the comfort of particular components may be improved.

Additionally, exterior surface 3376 may include only the textilesurface. That is, exterior surface 3376 may not be covered or layered bya textile membrane. In some forms, the exterior surface of particularsheets may or may not be layered with a textile membrane depending onthe design of a particular tube. For example, exterior surface 3374 ofinner layer 3352 may not be covered or lined with a textile membrane inorder to provide a comfortable surface to a patient. Exterior surface3376 of outer layer 3354, may however include a membrane for addedprotection or resistance to abrasion or other external forces. Further,because outer layer 3354 is spaced from the skin of a patient, it may beunnecessary to form outer layer 3354 with different surface propertiesalong interior surface 3356 and exterior surface 3376. For example,outer layer 3354 may be dipped into a thermoplastic or thermosetmaterial such that both surfaces are covered by a textile membrane. Themanufacturing costs may be diminished for outer layer 3354 in such aconfiguration as the time necessary to dip outer layer 3354 may be lessthan the time necessary to layer a single surface of a layer.

The overall weight of the positioning and stabilizing structure ispreferably less than 5 0g (e.g., less than 40 g or less than 30 g). Eachof the inner layer 3352 and outer layer 3354 may have a thickness ofless than 2 mm (e.g., less than 1 mm).

By utilizing sheets of textile, easy color customization may bepossible. For example, one sheet may be blue and the other sheet may bewhite. Different colors may allow for consumers to select a particularcombination that may increase the likelihood of the patient continuingto receive therapy utilizing the device.

By forming a headergear, tube, or conduit in such a manner the headgearmay be particularly formed to adjust or conform to the contours of theface of a patient. Rather than a straight cylindrical tube, the shape ofthe textile conduit may be determined by the how the inner layer and theouter layer are cut and attached to one another.

5.3.3.1.1.5 Patient Interface During Use

Patient interface 3000 as depicted in FIG. 4B-4D may be donned on thehead of the patient. Once in place, pressurized air is supplied throughair delivery tube 3348. From air delivery tube 3348, pressurized airpasses through either left arm 3302 or right arm 3304 or both arms. Theair then passes through the assembly connection port or ports 3154 and3155 and into cushion assembly 3150. In this manner air is supplied tothe patient.

In some forms, when pressurized air is passed through tube 3350, thecross-section of tube 3350 may be altered or changed. As shown in FIG.4F, 4G and 4H, inner layer 3352 is substantially planar. In some forms,during use inner layer 3352 may bulge or bend away from outer layer 3354between the joints 3312. That is, interior surface 3358 of inner layer3352 may have a positive curvature. In other words, exterior surface3374 of inner layer 3352 has a negative curvature between the joints3312. This curvature may assist in spacing other portions of inner layer3352 away from the face or head of the patient. For example, thecurvature may space the joints away from the face of the patient andincrease the comfort to the patient.

In some forms, outer layer 3354 may also expand when subjected topressurized air during use of patient interface 3000. Although outerlayer 3354 is formed in a predetermined shape, outer layer 3354 is not arigid structure and may expand when exposed to pressurized air. Thisexpansion may be in the material itself (for example, outer layer 3354may stretch) or the expansion may be caused by the edges of tube 3350moving toward each other. For example, the joints 3312 may move towardeach other causing the curvature of interior surface 3356 of outer layer3354 to become more positive than when in an unpressurized state. Thechanges in shape may be tuned for particular comfort and feel for thepatient during use.

Additionally, as described previously, the permeability of tube 3350 maybe tuned in specific areas. In one area, the tube 3350 may be completelyimpermeable to air, whereas in another area a particular quantity of airmay be permitted to transfer through tube 3350. For example, in someforms the permeability of tube 3350 may be tuned to allow a particularquantity of air to transfer from tube 3350 to the cheek of the patient.Additionally, the tube 3350 may be tuned such that air is only permittedto move through one layer of tube 3350 (i.e. toward the patient throughinner layer 3352 or away from the patient through outer layer 3354).

The textile construction of the tube 3350 allows the positioning andstabilising structure to be less resonant than conventional air deliverytubes and conduits, which is less disruptive to the patient and therebyfacilitates compliance with therapy.

5.3.3.1.1.6 Headgear Positioning

In certain forms of the technology, the stabilizing structure 3300comprises a mechanism for connecting a headgear strap to the sealforming structure 3100. The headgear strap may be connected directly orindirectly to the seal-forming structure 3100. As depicted in FIG. 4C,for example, a tab 3346 configured to connect to head strap 3420projects outwardly from tube 3350 in a generally posterior direction.The tabs 3346 may have holes or slots in them to receive the ends ofhead strap 3420. As depicted, however, strap 3420 may be secured betweeninner layer 3352 and outer layer 3354. That is, strap 3420 may besecured without any additional material beyond the material of innerlayer 3352 and outer layer 3354. For example, strap 3420 may be securedusing thermoset or thermoplastic material of inner layer 3352 and outerlayer 3354. Further, strap 3420 may extend into the chamber of tube 3350may be located outside of tube 3350. In other forms, strap 3420 may bein the form of a wire or string or other tubular structure that passesthrough an opening in tab 3346.

In some forms of the present technology, rear strap 3420 is adjustable.In some forms strap 3420 may include a hook and loop fastener such thata portion of rear strap 3420 that may pass through a hole in tab 3346and be secured to itself In some forms of the technology the angle ofthe strap 3420 relative to tube 3350 or patient's head is able to beadjusted to fit around the patient's head at a different location. Thisadjustability assists the headgear 3300 to accommodate different headshapes and sizes.

In certain forms of the technology, strap 3420 exerts a force on tube3350 to pull the tube in an at least partially posterior (e.g.rearwards) direction at the locations of tabs 3346. The strap 3420 mayalso exert a force on tube 3350 to pull the tube in an at leastpartially inferior (e.g. downwards) direction. The magnitude of theforce may be adjusted by altering the length of the strap 3420 betweenthe tabs 3346.

In some forms of the technology, such as the form shown in FIG. 4C, thedirection of the force applied to the tube 3350 by strap 3420 may alsobe altered. This direction may be altered by adjusting the angle of thestrap 3420 relative to tube 3350 or the patient's head. In some forms ofthe technology, the location at which strap 3420 exerts a force on thetube 3350 may be altered by adjusting the location at which strap 3420is secured to tube 3350.

In some forms of the technology, when worn by a patient, seal formingstructure 3100 tends to fall away or anterior, as well as down orinferior from the patient. Headgear 3300 is arranged to combat orcounteract these tendencies. Tube 3350, in conjunction with strap 3420provide both superior as well as posterior force so that in use sealforming structure 3100 remains in place. Further, tube 3350 along withstrap 3420 also provide addition forces posterior and superior so thatsealing layer 3102 provides a seal to the patients airways. Headgear3300 receives a downward force from seal forming structure 3100 that isat least partially counteracted by arm support 3314. Further, the topportion of tube 3350 allows headgear 3300 to remain in place along asuperior/inferior direction, while strap 3420 assists in maintaining theposition of headgear 3300 in an anterior/posterior direction.

The directions and magnitudes of the forces required for a secure fitand effective seal may vary between patients based on the position ofthe stabilizing structure 3300 on the head, which may vary due to, forexample, differences in head shapes and sizes. In some forms of thetechnology, the adjustability of the strap 3420 enables the forces to bebalanced for a range of head shapes and sizes to hold the headgear 3300in a comfortable position while maintaining an effective seal.

5.3.3.1.1.7 Connection Port Configurations

Tube 3350 includes a plurality of connection components that areconfigured to transfer air into and out of tube 3350. These connectioncomponents are integrated within the tube 3350 to provide a seamless orsmooth transition and connection to other components of the therapydevice. The connection components may be formed of a different materialthan tube 3350. In some forms the connection components are a hard orrigid plastic that resists bending or compressing. Such materials may beutilized to reduce the possibility of restriction of air through theconnection components.

Referring to FIGS. 4M and 4N connection port 3600 is depicted. As shown,connection port 3600 includes an upper surface 3602 and an oppositelower surface 3604. A channel 3606 extends between upper surface 3602and lower surface 3604 to guide air from intake 3608 to either side oftube 3350. Air is guided into and through intake 3608, through uppersurface 3602 and into channel 3606. The air then is guided along tube3350 to the mouth and/or nose of a patient.

Referring specifically to FIG. 4M, connection port 3600 is depictedwithin a portion of tube 3350. In some forms, connection port 3600 maynot be sealed or connected with the layers of tube 3350. That is,connection port 3600 may be able to slide along the interior surfaces ofthe layers of tube 3350. Rather than being sealed or mechanicallyconnected to the layers of tube 3350, connection port 3600 may berestricted from moving laterally by the shape of tube 3350. For example,the width of tube 3350 may taper or reduce such that connection port3600 is not able to slide to a large degree.

Referring to FIG. 40, an alternate form of the present technology of aconnection port is depicted. As shown, connection port 3701, includes anouter portion 3702 and an inner portion 3704. Inner portion 3704 may beinserted into tube 3350 such that inner portion 3704 is located betweeninner layer 3352 and outer layer 3354. Outer portion 3702 includes anextension that interacts with inner portion 3704. Outer portion 3702 ispositioned about an opening in tube 3350 and aligned with inner portion3704. Outer portion 3702 may be snapped into inner portion 3704 orotherwise secured to inner portion 3704. In this manner, outer layer3354 is secured between inner portion 3704 and outer portion 3702 ofconnection port 3701. Further, inner portion 3704 may be equipped with asupport to prevent inner layer 3352 from abutting outer layer 3354 atthe connection port. As shown, inner portion 3704 includes support 3706.Support 3706 is a cage-type structure that allows air to flow throughthe opening of connection portion 3700 and to the rest of tube 3350while also providing a gap or space between inner layer 3352 and outerlayer 3354 of tube 3350.

Additional connection components may connect tube 3350 to seal-formingstructure 3100. As shown there are two connection components attached totube 3350 that connect on either side of frame 3152 of seal-formingstructure 3100. Assembly connection port 3154 may be formed in a similarmanner as with connection port 3600. Further, assembly connection port3154 is configured to engage with an opening of seal forming structure3100 such that cushion assembly 3150 is in fluid connection with tube3350. By utilizing more than one connection component, air will bedelivered to a patient even if one side of tube is collapsed, such as bythe weight of the head of a patient when the patient sleeps on his orher side.

5.3.3.1.1.8 Method of Making Headgear Tube

The air delivery system of stabilizing structure 3300 such as tube 3350may be formed and manufactured using various techniques. In some forms,each of the layers or sheets of the textile used to form tube 3350 maybe pre-formed to have a particular cross-section. The layers or sheetsmay be coated with a silicone, polyurethane, thermoplastic, thermoset orother conformable material. This material may be the same materialutilized to form a textile membrane as discussed previously. In someforms, this layer may also act as the textile membrane. After receivingthe conformable material the sheets or layers may then be placed withina mold. Next the layers or sheets may be subjected to heat such that theconformable material melts. The heat is then removed from the layerssuch that the conformable material is allowed to cure. Then the layermay be removed from the mold such that the layer assumes the shape ofthe mold.

Referring now to FIGS. 8A-8F, an overview of one process used to form atube or air delivery system is depicted. As shown, mold 3800 is formedwith a substantially concave shape. The shape of mold 3800 may bealtered or modified depending on the desired shape of the tube that isto be produced. Textile sheet 3360 may be a textile sheet that is formedof the materials as described above. In some forms, textile sheet 3360may already include a textile membrane layer along a surface of textilesheet 3360. In the form depicted in FIGS. 8A-8F, however, textile sheet3360 does not already include a textile membrane. Textile sheet 3360 isthen placed within the mold as shown in FIG. 8B. After textile sheet3360 is adequately oriented another sheet is placed on top of textilesheet 3360. As shown in FIG. 8C and 8D, textile membrane 3362 isoriented against textile sheet 3360. Textile membrane 3362 may be amembrane that is formed of silicone, thermoplastic or other materials asdescribed previously with respect to a textile membrane. At the stepshown in FIG. 8D, the combination of textile sheet 3360 and textilemembrane 3362 may be subjected to heat such that membrane melts orpartially melts and/or otherwise adheres to a surface of textile sheet3360. The combined textile sheet 3360 and textile membrane 3362 may thenbe removed from mold 3800 after textile membrane 3362 has cured. Oncetextile membrane 3362 cures, textile membrane 3362 may assume the shapeof mold 3800 and therefore textile sheet 3360 may assume the shape ofmold 3800, forming inner layer 3352 described previously. It is notedthat one or both of inner layer 3352 and outer layer 3354 may bethermoformed to a predetermined shape. In other examples, neither of theinner layer 3352 and outer layer 3354 is thermoformed.

In some forms, multiple formed sheet and membrane combinations may beutilized to form a tube or portion of an air delivery system. As shownin FIGS. 8E and 8F, inner layer 3352 and outer layer 3354 are boththermoformed and may be combined to form tube 3350. Tube 3350 may have asteady state shape that includes a specific volume for the acceptance ofpressured air. Further, tube 3350 may be able to be folded and easilycollapsible for storage. Because tube 3350 includes textile membrane3362, tube 3350 may revert to the shape as shown in FIG. 8F even afterbeing folded or stored. Further, additional or different layers may beutilized in order to form more or less rigid structures. For example,outer layer 3354 may be formed to include a thermoset material such as afoam layer than when subjected to heat takes the form of mold 3800.Additional layers such as textile sheets, foam layers, textilemembranes, or other layers may be utilized to provide sufficient shaperetaining features or to provide sufficient rigidity or stiffness totube 3350 such that tube 3350 maintains its shape.

In other forms, a mandrel may be utilized. Rather than using anegatively shaped mold such as mold 3800, a mandrel may be covered byvarious layers such as inner layer 3352. Once covered by the desiredlayers, the mandrel may be heated or the layers may be heated toactivate the thermoplastic or thermoset material. Then the mandrel isremoved thereby forming inner layer 3352 or other layers in the shape ofthe particular mandrel shape.

In another form of the present technology, the membrane or conformablelayer may be a liquid or paste. In still further forms, the conformablelayer may not require heat to cure. For example, the conformable layermay cure when exposed to air, in a similar manner to a glue adhesive. Instill further forms, a chemical reaction may be utilized such as anepoxy or fiberglass resin. In some cases, the process of molding maylimit the shape and design of a particular component. In some forms,therefore, a laying up method may be utilized to form variouscomponents. Laying up includes a mold of a particular shape. A layersuch as a fabric or textile layer may be placed into the mold. Then aresin, membrane material, or other material is placed over the layer.The resin or other conformable material is then cured such that theshape of the layer corresponds to the shape of the mold. In some forms,a releasing agent may be placed between the fabric layer and the mold toassist in providing an easier removal of the layer from the mold. Onceremoved from the mold, the layer may maintain or retain the shape of themold.

As shown in FIGS. 8G-8K, a tube 3363 may be formed using the techniquedescribed above. As shown in FIG. 8G, textile sheet 3360 is placed inmold 3800. In FIG. 8H, textile membrane 3362 is placed along textilesheet 3360. In this form, textile membrane 3362 may be administered inliquid form as opposed to the method depicted in FIG. 8C. As shown inFIG. 81, textile membrane 3362 is spread along textile sheet 3360 suchthat all appropriate portions of textile sheet 3360 are covered bytextile membrane 3362. After textile membrane 3362 has cured by eitherheat or other manner, inner layer 3352 that includes textile sheet 3360and cured textile membrane 3362 is removed from mold 3800. In a similarmanner as with respect the tube 3350 as shown in FIGS. 8A-8F, innerlayer 3352 may be combined with outer layer 3354 to form tube 3350.

After these two layers (for example, inner layer 3352 and outer layer3354) are formed they may be joined along longitudinal edges to form achamber. In some forms, the two layers may be joined using a glue orother adhesive. In other forms, the layers may be joined usingmechanical fasteners such as nails, screws, or buttons. In other forms,the two layers may be stitched or sewn together. In still further forms,the two layers may be welded together. In regard to welding, the twolayers may be welded using high frequency or radio frequency welding. Instill further forms, a hot knife may be used to cut the layers and whencutting may also form a seal between the two layers as portions of thetwo layers melt and cure, thereby forming a seal between the first layerand the second layer.

In some forms, welded connections may be used in various locations of atextile conduit. In some forms, welded connections may be utilized toconnect other components to the textile conduit or to connect thetextile conduit to other components. Rather than relying on physicalfasteners such as thread, clips, snaps or the like, components may besecured to one another by utilizing various types of welding. By usingwelding, there may be fewer bulky connections. Further, by utilizing awelding connection technique, there may not be a need for additionalconnection components. For example, a connection between the textiletube and an adaptor or connector may be formed by placing a portion of alayer of the textile conduit around the adaptor such that the membraneof the layer is against the adaptor. The combination of the layer andthe adaptor may then be subjected to heat such that the membrane meltsor conforms to the adaptor. When the membrane cures, a secure connectionmay be formed between the layer and the adaptor.

Referring to FIGS. 8L and 8M, the technique described above may beapplied to more complicated shapes. Rather than utilizing a mold andthermoplastic or thermoset material to only shape the internal crosssection, the mold and thermoplastic material may also be used to form athree-dimensional shape over the length of a component. That is, inaddition to forming a chamber, the mold may be used such that tube 3350can be bent or turned along three axes and maintain this shape withoutadditional support. As shown in FIG. 8L, mold 3802 includes a groove oraccommodating portion 3804 that extends in a first direction D1 and aperpendicular direction D2. Textile sheet 3360 may be cut to aparticular shape and then placed along accommodating portion 3804 ofmold 3802. For simplicity, textile sheet 3360 may already be layeredwith a thermoset or other conformable membrane. As shown in FIG. 8M,textile sheet 3360 is subjected to heat such that the membrane melts orconforms to the shape of accommodating portion 3804. Once cured, textilesheet 3360 is removed from mold 3802 and retains the shape ofaccommodating portion 3804.

Tube 3350 may be formed using sheets that are molded in mold 3802 (SeeFIGS. 4L-1 to 4L-4). For example, a second sheet similar to textilesheet 3360 may be formed and joined with textile sheet 3360 in a similarmanner as depicted in FIGS. 8A-8F. As shown in FIGS. 4L-1 to 4L-4, tube3350 may be oriented in various directions. That is, tube 3350 may beformed or conformed to return to a three dimensional object. By formingtube 3350 as a three dimensional object, the amount or quantity ofcreases or bends in tube 3350 may decrease when used. For example,rather than requiring a patient to bend or twist tube 3350 to conform tothe face of the patient, tube 3350 may be pre-formed with a bend or atwist. Kinks that may decrease airflow through tube 3350 may be reducedby providing a bend or turn naturally within the shape of tube 3350 asopposed to shaping the tube 3350 in a separate step afterwards. As seenin FIGS. 4A-4D, when tube 3350 is used by a patient, tube 3350 may beshaped to correspond to the shape of the face and head of a patient. Byparticularly shaping tube 3350 during the manufacturing process,pressure points may be reduced.

Additionally, in some forms, only a first sheet such as textile sheet3360 is molded or formed within a mold such as mold 3802. A sheet thatis not pre-molded may be attached to the molded sheet such that thesecond sheet conforms to the shape of textile sheet 3360.

The textile membrane may be located along various surfaces of thetextile. The textile may be dipped into a material such that all sidesare covered or layered with the membrane. Other forms of the textile maycoat or layer a single surface of the textile. In some forms, themembrane or curing material may only be located along a single surfaceof the fabric layer. That is, in some forms, a first surface of thefabric material may be coated by another material such as a thermosetand a second surface may be an uncovered fabric. That is, there may bedifferent properties on either side of the material. The membrane alsomay be formed of various materials. In some forms the textile membraneis formed of silicone, and in other forms the membrane is formed ofpolyurethane. In other forms, different materials may also be utilized.

In some forms, the textile membrane may be located along a flat orplanar sheet of textile. That is, sheets of textile may be manufacturedand include a layer of membrane material along a surface of the textile.In some forms, the membrane may be layered onto a textile in asheet-like manner. In other forms, the membrane may be spread about thetextile while in liquid or semi-liquid form such that the membranecovers a surface or a portion of the surface of the membrane. Themembrane may then cool or dry such that the membrane cures along asurface of the textile.

In some forms, various methods and techniques may be utilized to formthe various components of a therapy device. In some forms, flat orplanar materials may be manipulated to form three dimensional structuresfor utilization in a therapy device. These materials may be customformed or tuned to allow for greater comfort when compared to otherforms. In some forms, the seal forming structure may be formed of atextile material. This material may be less obtrusive, more comfortable,and less heavy than other configurations. Additionally, other componentsmay also be formed of planar materials that are manipulated to formthree dimensional structures. For example, tubing may be formed fromplanar materials. Further, other components that contain or arecontacted by pressurized air may also be formed from planar materials.In addition to components that contain or guide pressurized air, othercomponents such as straps may be formed from planar materials that aremanipulated to form three dimensional structures.

Known patient interfaces typically also include separate headgear andair delivery components that are used to locate and supply breathablegas to a mask or the like. Known headgear typically includes an assemblyof elastic (or inelastic) straps, buckles, locks, and/or clips. Knownair delivery components typically include 15-22 mm diameter spiralreinforced tubing and swivel connectors. These known arrangements ofheadgear and air delivery components can be difficult to use for thosewho are less dexterous and/or unfamiliar with them. These knownarrangements of headgear and air delivery components can also beuncomfortable or impractical to lie on.

5.3.3.1.1.8.1 Cut and Seal Method

Components may be formed and connected using various methods andtechniques. In one form multiple components may be formed using a cutand seal method. In this method each of the components may be cut to aparticular shape. In some forms, the components may then be layered ontop of one another after cutting has taken place. In other forms,multiple layers may be layered on top of one another and then all of thelayers may be cut at once. In some forms, during the cutting process thelayers also may be connected to one another. For example, in some formsa hot knife may be used that both cuts and fuses the layers together. Insuch a method the time required to manufacture a particular componentmay be reduced when compared to other methods of manufacturing.

The sheets utilized to form the textile conduits may be less than 750 mmby 350 mm. In other forms, the sheets may be larger or smaller than orequal to 750 mm by 350 mm. The small size of the sheet may permitmultiple textile conduits or tubes to be formed within a small location.By decreasing the footprint of the elements used to form the textileconduits the cost of manufacturing may decreased because less space thatrequires rent or upkeep is required.

Referring to FIGS. 9A-9E, the present form of the technology is depictedsuch that a tube is formed through the use of a cut and seal method.Outer covering 3366, tube sheet 3364, and textile sheet 3360 aredepicted. As shown, each of the sheets include a textile membrane orother fusible membrane as described in previous forms. As describedpreviously, outer covering 3366 may be utilized as an exterior layer andtherefore may have different material properties than tube sheet 3364.Textile sheet 3360 may be an interior layer and formed of material thatis soft against the skin of a user on an exterior surface, while alsoincluding a textile membrane configured to reduce the quantity of airthat passes through textile sheet 3360. In some forms exterior surface3374 of textile sheet 3360 may be configured to rest against the skin ofa patient.

As shown in FIGS. 9A and 9B, the layers are stacked upon each other. Insome forms of the present technology, a guide may be placed upon thelayers that indicates the desired cut location. In some forms textilesheet 3360 may be pre-stretched prior to assembly. For example, textilesheet 3360 may be stretched horizontally, vertically, or bothhorizontally and vertically to provide a particular configuration. Afterthe upper and lower layers are joined, the tension may be released fromtextile sheet 3360 such that it assumes an unstretched position. Thismay cause the upper layer to bend as textile sheet 3360 is unstretched.Therefore a particular shape may be realized by pre-stretching the lowerlayer during manufacturing and then releasing the tension.

In FIG. 9B a laser 3382 is utilized to both cut and seal the varioussheets of material. In some forms, welding techniques such asHigh-Frequency (HF) welding or Radio Frequency (RF) welding may also beutilized to form a seal. Additionally, in other forms a hot knife may beutilized. As the material is cut, the thermoset, thermoplastic, orconformable membrane adjacent to the cut line may melt or changeproperties. The melting of the membrane allows for the membrane tointeract with adjacent layers. For example, the membrane of outercovering 3366 may interact with the upper surface of tube sheet 3364.Likewise, the membrane of tube sheet 3364 may interact with the lowersurface of outer covering 3366. Further, the membrane of tube sheet 3364may interact with the interior surface of textile sheet 3360. In otherforms, tube sheet 3364 may only include a membrane along the lowersurface and outer covering 3366 may include a membrane that melts andinteracts with the upper surface of tube sheet 3364. After the membraneshave melted, they may cure. Upon curing the sheets are connected to oneanother along the cut lines. In this manner a tube such as tube 3450(See FIG. 9C) is formed. In contrast to tube 3350, tube 3450 may nothave a thermoformed inner and outer layer. Rather, outer layer 3354 andinner layer 3352 may be connected along the outer edges along a jointand not further subjected to heat to maintain a particularcross-sectional shape when not exposed to internal air pressure or otherforces.

In some forms, additional components may be incorporated into thetextile conduit during the formation of the textile conduit. Forexample, in some forms connection components may be incorporated intothe textile conduit during the manufacturing process. In some forms, anelbow or tube connection may be placed along the inner layer before theouter layer is secured to the inner layer. After the tube connection isplaced along the inner layer the outer layer is lined over the innerlayer. Next a connection is formed between the inner layer and the outerlayer. As described previously, the connection may be formed by variouswelding techniques. In some forms, the connection between the innerlayer and the outer layer may also secure the tube connection. In otherforms, however, the tube connection may be trapped within the chamber ofthe conduit, however, the tube connection may not be physically securedto either the inner layer or the outer layer. That is, in some forms thetube connection may be restricted from movement by friction or spacerestrictions within the chamber. In other forms, the tube connection maybe clipped into place, such as described previously.

As shown, connection port 3600 is arranged between tube sheet 3364 andtextile sheet 3360. Additionally, assembly connection ports 3154 and3155 may also be similarly situated. Connection port 3600 and assemblyconnection ports 3154 and 3155 are sandwiched between tube sheet 3364and textile sheet 3360. Once sealed as shown in FIG. 9B, the connectionports may be located within tube 3450 without requiring another step toinsert or located the connection portions within the tube.

Referring to FIGS. 9C through 9E, tube 3450 is depicted in variousstates. As shown in FIG. 9D, tube 3450 is depicted in a steady state andnot subjected to internal air pressure. In this form, as shown in thecross section, outer layer 3354 and inner layer 3352 lie substantiallyplanar along the surface of one another. That is, in contrast topreviously discussed forms of the present technology, tube 3450 is notpre-formed to have a particular cross section. Tube 3450 therefore doesnot occupy as much space when not being used as compared to other formsof the technology. Further, tube 3450 may be easily storable such thattube 3450 may be a convenient tube with which to travel.

As shown in FIG. 9E, once subjected to internal pressure, such as airpressure from a therapy device, tube 3450 may expand or open. Air may beforced through connection port 3600 such that the air fills the internalchamber of tube 3450. Air may then pass to the ends of tube 3450 and toanother connection mechanism such as assembly connection ports 3154 and3155 or to the nose or mouth of a patient. Referring particularly to thecross section of FIG. 9E, as shown, both tube sheet 3364 and outercovering 3366 are located along the upper portion of the cross sectionwhereas textile sheet 3360 is located along the lower portion of thecross section. Because connection port 3600 and assembly connectionports 3154 and 3155 were placed between tube sheet 3364 and textilesheet 3360, the air flow from the therapy device is directed toconnection port 3600 and assembly connection ports 3154 and 3155 andtherefore does not extend between tube sheet 3364 and outer covering3366. In other forms, the sheets may be designed such that air ispermitted to pass through any of the layers. Additionally, theconnection port 3600 and assembly connection ports 3154 and 3155 may belocated in various positions depending on the particular circumstancesor design requirements.

In some forms, inner layer 3352 and/or outer layer 3354 may be formed ofinextensible material. That is, in some forms inner layer 3352 and outerlayer 3354 may not stretch when subjected to internal air pressure, butmay still inflate such as depicted in FIG. 9E. In other forms, innerlayer 3352 and/or outer layer 3354 may be formed of resilient materialthat stretches when subjected to internal pressure. In still furtherforms, inner layer 3352 may include a textile that does not stretchwhile outer layer 3354 includes a textile that stretches. For example,the stretch or extensibility properties of the inner layer 3352 and theouter layer 3354 may be different.

When formed in the manner as described, outer layer 3354 may be cut orslit such that outer layer 3354 extends around intake 3608 of connectionport 3600. In a similar manner inner layer 3352 may be cut or slit suchthat inner layer 3352 extends around assembly connection ports 3154 and3155. Outer layer 3354 may be cut or sliced before or after outer layer3354 is secured to inner layer 3352. In some forms, outer layer 3354 maythen be subjected to heat in a particular location such that themembrane melts and outer layer 3354 conforms to intake 3608 ofconnection port 3600. Then the membrane associated with tube sheet 3364is allowed to cure such that a secure connection is formed between outerlayer 3354 and the connection port 3600. A similar arrangement may beutilized with respect to inner layer 3352 and assembly connection ports3154 and 3155.

In other forms, outer layer 3354 and inner layer 3352 may be flexible,stretchable, and resilient such that outer layer 3354 and/or inner layer3352 are able to be stretched around intake 3608 of connection port 3600or similar intakes of assembly connection ports 3154 and 3155. Becauseouter layer 3354 includes a membrane that contacts connection port 3600,the membrane may assist in providing an adequate seal between outerlayer 3354 and connection port 3600. That is, the resiliency of outerlayer 3354 may cause outer layer 3354 to contract around the opening ofconnection port 3600. The resiliency of outer layer 3354 in combinationwith the membrane allows for a seal to be formed between connection port3600 and outer layer 3354. Similar to a rubber band, outer layer 3354may press against intake 3608 through friction rather than by apermanent connection. This friction fit may restrict the movement ofconnection port 3600 such that connection port 3600 remains in aparticular location.

Additionally, the connection between outer layer 3354 and connectionport 3600 may be adjusted such that a specific quantity of oxygen or airis able to leak through the connection. This specific leakage may removethe need to include a separate valve that allows for excess air, oxygen,or waste air to be disposed of during use.

In other forms, tube 3450 may be formed such that tube 3450 has apredetermined shape such as tube 3350. For example, inner layer 3352 andouter layer 3354 may be arranged around a mandrel and then subjected toheat to form a particular cross section. Then the layers may be cut andsealed so that in addition to being thermoformed, inner layer 3352 andouter layer 3354 are connected to one another during the cuttingprocess.

5.3.3.1.2 Strap Rigidity

In some forms, components may be formed utilizing various quantities ofa conformable membrane. In some forms, a conformable membrane may beparticularly placed along various surfaces. The conformable material maybe utilized to provide specific reinforcement in various areas of astrap or other component. For example, a strap such as strap 3420 isutilized to assist in securing patient interface 3000 to the face of apatient. In some forms, particular areas of a strap may requireincreased or additional support when compared to other portions of thestrap. Further, in some forms, the stretch or elasticity of the strapmay be limited by utilizing the silicone or polyurethane membrane.

Referring to FIGS. 5A-5E a strap is depicted. The strap includes aninner layer, a membrane layer, and an outer layer. Although depictedwith an outer layer, it is not necessary that an outer layer beincluded. That is, in some forms, elastic inner layer 3422 and membranelayer 3424 may be utilized without outer layer 3426. As shown in FIG.5A, strap 3420 may interact with tube 3350 to secure patient interface3000 in place with respect to a patient. Membrane layer 3424 is depictedwith substantial thickness in the figures for ease of viewing. Membranelayer 3424 may be substantially thinner than either outer layer 3426 orinner layer 3422. For example, membrane layer 3424 may be less than 10%of the thickness of either outer layer 3426 or inner layer 3422

Referring to FIG. 5B, a portion of strap 3420 is depicted in isolationfrom the rest of patient interface 3000. As shown, strap 3420 includesouter layer 3426 and inner layer 3422. Membrane layer 3424 is locatedbetween the layers, and in some forms connects the layers to oneanother. That is, strap 3420 may be exposed to a heat source such thatmembrane layer 3424 melts or changes forms and cools such that innerlayer 3422 and outer layer 3426 are connected to one another. As shownin FIG. 5B membrane layer 3424 does not extend the full length of innerlayer 3422. In other forms, membrane layer 3424 may extend the fulllength of inner layer 3422. In further forms, one of the layers may notextend the full distance of strap 3420. For example, in some forms,outer layer 3426 may only extend along strap 3420 the same or similardistance as does membrane layer 3424. In that example, the entire lengthof outer layer 3426 may be secured to inner layer 3422 through the useof membrane layer 3424. Further, in some forms, the membrane may beadhered along the entire length of the shortest layer. Then the twolayers may be combined and adhered to one another using a thermoplasticor thermoset material such as membrane layer 3424.

As shown in FIG. 5C, a portion of inner layer 3422 is layered withmembrane layer 3424. In some forms, membrane layer 3424 may be formed ofthe same material as the textile membranes discussed with respect totube 3350. By utilizing the same material in various parts of a patientinterface, the manufacturing costs may be reduced when compared to otherforms. Inner layer 3422 may be formed of an elastic or stretchablematerial that is conformable to the shape of a head of a patient.Additionally, outer layer 3426 may also be made of the same or similarmaterial in the same or similar configuration. The layers may be formedof natural or synthetic materials. In some forms the layers may betextiles whereas in other forms the layers may be rubber or plasticcomponents. Further, although depicted as the same or similar materialwith the same or similar properties, inner layer 3422 and outer layer3426 may have different properties such as stretch, rigidity,flexibility, and other properties. The materials for each layer may bechosen depending on the particular properties desired for strap 3420.

Referring to FIGS. 5D and 5E, inner layer 3422 has a differentstretchability than outer layer 3426 in areas in which membrane layer3424 not present. For example, when subjected to a tensile force T,inner layer 3422 stretches a first distance 3428. As shown, membranelayer 3424 along with outer layer 3426 stretch second distance 3430 whensubjected to the same tensile force T. Second distance 3430 is smallerthan first distance 3428. Membrane layer 3424 therefore may limitstretching in the particular area on which the membrane layer 3424 isapplied. That is, although permitted to stretch, membrane layer 3424 mayreduce the distance that inner layer 3422 or outer layer 3426 is able tostretch. This type of configuration may be utilized in particular areasthat require stepped stretchability to provide adequate support to theapparatus. Although depicted with outer layer 3426, in some forms of thepresent technology, outer layer 3426 may not be utilized. Inner layer3422 may be used for the strap without using another layer such as outerlayer 3426. In such a configuration, the strap may be oriented such thatmembrane layer 3424 faces away from the patient. In this manner, thesoft texture of inner layer 3422 may be against the face of a patient.Membrane layer 3424 may therefore be utilized to limit stretch without acovering such as outer layer 3426.

In addition to controlling the stretch rate of particular components,the use of membrane layer 3424 may also control the rate of restoration.That is, membrane layer 3424 may increase the ability of an elastic bandsuch as strap 3420 to return to its original, unstretched state.

In some forms, the membrane layer 3424 may be utilized to providestructural support a strap. In some forms, a strap may twist or rotateduring use such that the strap is out of position and causes creases anddiscomfort to the patient. In such instances, a membrane may be utilizedto support the strap and to resist that strap from rotating or twistingduring patient.

Various straps may be utilized to support a cushion assembly such thatthe cushion assembly provides adequate sealing to the nasal or mouthareas of a patient. As shown in FIG. 5F, head strap 3432 is shown inconjunction with tube 3434 of an alternate patient interface 3436.

Referring to FIG. 5G a head strap component is depicted. Head strap 3432may include various features as discussed previously. Referring to FIG.5H, an exploded view of head strap 3432 is depicted. As shown, headstrap 3432 includes interior layer 3437, exterior layer 3438, straps3439-3442 and pad 3443. Interior layer 3437 and exterior layer 3438encompass or sandwich a portion or all of the components. As shown,interior layer 3437 and exterior layer 3438 completely sandwich pad 3443and encompass a portion of straps 3439-3442. In some forms, interiorlayer 3437 and/or exterior layer 3438 may be layered with a membrane orsilicone or polyurethane layer such as described previously withreference to tube 3350. The interior layer 3437 and exterior layer 3438may be aligned and then subjected to heat such that the membrane betweenthe interior layer 3437 and exterior layer 3438 melts and then joins thelayers together. As shown, the interior layer 3437 and exterior layer3438 also may adhere or join to the pad 3443. In other forms, themembrane layer may be absent in the area of the pad 3443. That is, thepad 3443 may be located in a pocket between interior layer 3437 andexterior layer 3438, however the pad 3443 may not be physically securedto the interior layer 3437 or the exterior layer 3438. Further, in someforms, the straps 3439-3442 may be secured using an adhesive. However,in other forms, the straps 3439-3442 are secured to the interior layer3437 and the exterior layer 3438 through the membrane.

The components of head strap 3432 may be spaced in various orientations.As shown in FIG. 5G, strap 3442 is spaced from strap 3441 by a portionof interior layer 3437 and a portion of exterior layer 3438. Similarly,strap 3442 is spaced from pad 3443 by a portion of interior layer 3437and exterior layer 3438. Various other configurations can be utilized.For example, in some forms, strap 3442 may contact strap 3441. In stillfurther forms, strap 3442 and strap 3441 may be a unitary piece. Othervariations are possible as well. For example, pad 3443 may be larger orsmaller, or may not be present. By varying the size, shape, andorientation of the various components, the feel of the component may bechanged and customized. As shown, there may be various different stretchzones of head strap 3432. Zone X1 includes the straps 3439-3442 and theyhave a first stretchability, and in some forms may be substantiallyinextensible. The second zone is zone X2 which includes the straps3439-3442 and a portion of interior layer 3437 and exterior layer 3438.This has a second stretchability which may also be substantiallyinextensible. The third zone is zone X3 between the end of the straps3439-3442 and the pad 3443. This has a third stretchability. And finallythe last stretch zone is zone X4 which includes the pad 3443 and theinterior layer 3437 and the exterior layer 3438. These various areas maybe altered depending on the manufacturer's intent or desire for variousproperties.

The configuration as shown in FIG. 5G allows for various properties tobe present in a single head strap 3432 without the need for variousconnection components that add bulk and may be uncomfortable. Byintegrating a membrane as a joining material, the weight of the headstrap also may be reduced when compared to other forms.

5.3.3.1.3 Headgear Tube or Conduit Having an Impermeable Layer

FIGS. 33A-33F show further examples of the headgear tube, gas deliverytube, or conduit 5600 according to the present technology. The conduit5600 may include an elongate, tubular textile portion 5610 having anexterior surface and an interior surface. The conduit 5600 may includean impermeable layer 5603 joined to the interior surface of theelongate, tubular textile portion 5610 at an interface 5606, theimpermeable layer 5603 being impermeable to air. The impermeable layer5603 may be constructed from a single, homogeneous piece of material,such as a polymer. The impermeable layer 5603 may be cirumferentiallycontinuous. The conduit 5600 may be constructed without any seamsextending from the exterior surface. A passage 5604 for the flow ofpressurized air may be formed within the impermeable layer 5603. Theimpermeable layer 5603 may include multiple layers of polymers, andthose polymers may be different from one another. Alternatively, theimpermeable layer 5603 may be formed from a single polymer.

The conduit 5600 of the examples shown in FIGS. 33A-33F may be similarto other conduits or tubes disclosed herein. For example, the materialsand methods disclosed elsewhere herein may be used to form the conduit5600. The conduit 5600 of the present examples, however, may not includethe joints 3312, e.g., shown in FIGS. 4F-4K, that form edges extendingoutward from the conduit 5600. Such edges may allow for the introductionof contaminants into the exposed lateral surfaces, e.g., of the textilelayers, and the present examples are designed to reduce or eliminatesuch exposed surfaces.

The elongate, tubular textile portion 5610 of the conduit 5600 mayinclude an outer textile portion 5601 and an inner textile portion 5602that are connected by joints 5605. The elongate, tubular textile portion5610 of the conduit 5600 may be constructed from a single piece oftextile material that is joined at opposite edges to form a tube withone seam. Alternatively, the elongate, tubular textile portion 5610 maybe constructed from a single piece of textile that is cirumferentiallycontinuous and has no joints 5605, e.g., formed by circular weaving orknitting or 3-D printing or knitting.

The elongate, tubular textile portion 5610 of the conduit 5600 may beconstructed from intertwined strands of fibers and/or filaments. Theelongate, tubular textile portion 5610 of the conduit 5600 may beconstructed from a spacer fabric. The elongate, tubular textile portion5610 may be formed by weaving. The elongate, tubular textile portion5610 may be formed by knitting. The elongate, tubular textile portion5610 may be constructed from a non-woven fabric. The elongate, tubulartextile portion 5610 may comprise synthetic fibers and/or filaments. Theelongate, tubular textile portion 5610 may be constructed from nylon.The elongate, tubular textile portion 5610 may be constructed frompolyester. The outer textile portion 5601 and the inner textile portion5602 may be constructed from different textile materials. The innertextile portion 5602 and the outer textile portion 5601 may be joinedtogether without stitching. The inner textile portion 5602 and the outertextile portion 5601 may be joined with ultrasonic welding. Ultrasonicwelding may also be used to join opposite edges of the textile materialthat is wrapped to form the elongate, tubular textile portion 5610.

Similar to other examples disclosed herein, the conduit 5600 may includethe impermeable layer 5603 to maintain the flow of air at a desiredpressure above ambient as the air travels within the passage 5604 fromthe air circuit 4170 to the plenum chamber 3200, to ensure that moisturewithin the passage 5604 remains within the passage 5604, and to minimizethe ability of contaminants to enter into the flow of pressurized airtraveling through the passage to the patient. The elongate, tubulartextile portion 5610 may be formed as described above, and then theimpermeable layer 5603 may be formed within the elongate, tubulartextile portion 5610 by blow-molding or spraying. Alternatively, theimpermeable layer 5603 may include two portions, which correspond to theouter textile layer 5601 and the inner textile layer 5602, respectively.The impermeable layer 5603 may be extruded and then introduced into theinterior of elongate, tubular textile portion 5610, and then theimpermeable layer 5603 may be joined to the interior surface of theelongate, tubular textile portion 5610, e.g., via blow molding. Forexample, the method to form such a conduit 5600 may include forming theelongate, tubular textile portion 5610 by intertwining strands, asdisclosed elsewhere herein, to form a tubular structure, the impermeablelayer 5603 may be extruded (e.g., as a parison) and passed into theelongate, tubular textile portion 5610, and then the impermeable layer5603 may be expanded and joined to the interior of the elongate, tubulartextile portion 5610, e.g., via blow molding.

The impermeable layer 5603 may be joined to the interior surface of theelongate, tubular textile portion with a mechanical connection. Theimpermeable layer 5603 may be joined to the interior surface of theelongate, tubular textile portion with a chemical bond. FIGS. 33C to 33Fshow how the impermeable layer 5603 may be bonded coextensively with theouter textile layer 5601 and the inner textile layer 5602 so that thereare no gaps between the impermeable layer 5603 and the outer textilelayer 5601 and the inner textile layer 5602.

The impermeable layer 5603 may be formed from a polymer, which may beone of: Liquid Silicone Rubber (LSR), Low Density Polyethylene (LDPE),High Density Polyethylene (HDPE), Polyethylene Terephtalate (PET),Polypropylene (PP), and Polyvinyl Chloride (PVC). The impermeable layer5603 may be constructed from a single, homogeneous piece of material.The impermeable layer 5603 may be sufficiently flexible, e.g., to allowthe conduit 5600 to conform to the shape of the patient's head in use.

The exterior surface of the conduit 5600 may have a curved, non-patientcontacting side and a substantially flat patient contacting side. Theconduit 5600 may have an oval-shaped cross-section. The conduit 5600 mayhave a circular cross-section.

The thickness of the impermeable layer 5603 may be substantiallyconsistent. The thickness of the impermeable layer 5603 may vary in adirection parallel to the elongate, tubular textile portion's 5610longitudinal axis. The thickness of the impermeable layer 5603 may varycircumferentially.

Additionally, FIG. 33D shows how the joints 5605 connect the outertextile layer 5601 and the inner textile layer 5602 directly without anypart of the impermeable layer 5603 within the joints 5605. This isdistinct from the examples in FIGS. 4F and 4V in which two sheets ofmultiple layers of material are joined along opposite edges to form thetube such that the impermeable layer of each sheet is jointed directlyto the other. In the example shown in FIG. 33D, the joints 5605 connectthe outer textile layer 5601 and the inner textile layer 5602 separatelyfrom the impermeable layer 5603. The impermeable layer 5603 is notrequired to connect the outer textile layer 5601 and the inner textilelayer 5602. There is no impermeable layer 5603 between the outer textilelayer 5601 and the inner textile layer 5602 within the joints.

It should also be understood that other conduits, such as the aircircuit 4170 that connects the RPT device 4000 to the patient interface3000, may include these features.

5.3.3.1.4 Headgear Tube or Conduit Having an Impermeable Layer with aConnector

FIGS. 33G and 33H show further examples of the headgear tube, gasdelivery tube, or conduit 5600 according to the present technology. Theconduits 5600 of these examples may include any one or more of thefeatures described in the preceding section and elsewhere herein.Additionally, these examples of the present technology may furtherinclude a connector 5620 molded with the impermeable layer 5603. Theconnector 5620 may include a snap feature 5621 to provide tactile and/oraudible feedback of the connection of the connector 5620 to anotherstructure such as a plenum chamber 3200. The snap feature 5621 may becantilevered from the conduit 5600 so that it can flex upon contact withanother component to facilitate the connection. There may be one ormore, e.g., two, connectors 5620 formed around the perimeter of theconduit 5620 and the connectors 5620 may be in opposition to oneanother. However, it should be understood that gaps between theconnectors 5620 may be necessary to allow the connectors 5620 to flextowards one another to enter a corresponding female connector.

It should also understood that a female connector 5620 version of thepresent technology is also envisioned. The connector of this versionshould be sufficiently thick so that the corresponding notches may beformed to receive connecting structures of a male connector.

The connector 5620 may be formed in one piece and in one step with theimpermeable layer 5603. For example, the connector 5620 may be formed ina corresponding portion of the mold outside of the elongate, tubulartextile portion 5610 but within the overall mold by allowing a portionof the extruded parison to protrude beyond the interior of the elongate,tubular textile portion 5610 and then blow molding the impermeable layer5603 and the connector 5620 together. Thus, the impermeable layer 5603and the connector 5620 may be formed from a single piece of homogeneousmaterial, such as the materials described for the impermeable layer 5603above.

FIG. 33H shows yet a further version of the present technology in whichthe connector is formed as described in the preceding paragraph.Additionally, this example includes a connector insert 5622. The snapfeature 5621 may be formed upon the connector insert 5622. The connectorinsert 5622 may also include tabs 5624 projecting therefrom to engageportions of the material of the connector 5620 to form correspondingnotches 5623 upon molding that receive and form a mechanical connectionwith the tabs 5624. The tabs 5624 may be formed with an undercut suchthat the material of the connector 5620 may spread into the undercutduring molding to facilitate the mechanical connection.

The connector insert 5622 may be formed from a harder material, such asrigid plastic, than the connector 5620 and the impermeable layer 5603 toensure a firm connection with the patient interface 3000, for example.The harder material may also allow for louder and more forceful feedbackwhen the snap connection is engaged or disengaged.

It should also be understood that one or more such connectors 5620 maybe formed at each end of the conduit 5600.

It should also be understood that other conduits, such as the aircircuit 4170 that connects the RPT device 4000 to the patient interface3000, may include these features.

5.3.3.2 Positioning and Stabilising Structure According to AdditionalExamples of the Present Technology

Additional examples of the positioning and stabilising structure aredescribed below. It should be noted that the features described belowmay be used with or combined with features described in other examplesof this disclosure. For example, the tubes described below may be usedwith the cushion modules/cushion assemblies described in other examples,and vice versa. Moreover, individual features of any of the structuresdescribed in any example may be used with or combined with features inother examples.

5.3.3.2.1 Headgear Tubing

As shown in FIGS. 10 and 11, a non-invasive patient interface 9000,10000 in accordance with examples of the present technology may comprisethe following functional aspects: a seal-forming structure 9100, aplenum chamber 9200, a positioning and stabilising structure 9300, atleast one vent 9400, 9400-1 and one form of connection port 9600 forconnection to an air circuit (e.g. the air circuit 4170 shown in FIGS.1A- 1C). In this example, the seal-forming structure 9100 and the plenumchamber 9200 are provided by a cushion module 9150. The cushion module9150 in this example is a cradle cushion module. In other examples itmay be a nasal pillows cushion module or another type of cushion module.

In some forms of the present technology, the positioning and stabilisingstructure 9300 comprises one or more tubes 9350 that deliver pressurisedair received from a conduit forming part of the air circuit 4170 fromthe RPT device to the patient's airways, for example through the plenumchamber 9200 and seal-forming structure 9100. In the forms of thepresent technology illustrated in FIGS. 10 and 11, the positioning andstabilising structure 9300 comprises two tubes 9350 that deliver air tothe seal-forming structure 9100 from the air circuit 4170. The tubes9350 are an integral part of the positioning and stabilising structure9300 of patient interface 9000 to position and stabilize theseal-forming structure 9100 of the patient interface to the appropriatepart of the patient's face (for example, the nose and/or mouth). Thisallows the conduit of air circuit 4170 providing the flow of pressurisedair to connect to a connection port 9600 of the patient interface in aposition other than in front of the patient's face which may beunsightly to some people. While a pair of tubes 9350 have someadvantages (described below), in some examples, the positioning andstabilising structure 9300 comprises only a single tube 9350 configuredto overlie the patient's head on one side. A strap or other stabilisingcomponent may be provided to the other side of the patient's headbetween the top end of the single tube 9350 and the seal-formingstructure 9100, to provide balanced forces on the seal-forming structure9100.

Since air can be contained and passed through headgear tubing 9350 inorder to deliver pressurised air from the air circuit 4170 to thepatient's airways, the positioning and stabilising structure 9300 may bedescribed as being inflatable. It will be understood that an inflatablepositioning and stabilising structure 9300 does not require allcomponents of the positioning and stabilising structure 9300 to beinflatable. For example, in the examples shown in FIGS. 10 and 11, thepositioning and stabilising structure 9300 comprises the headgear tubing9350, which is inflatable, and the strap 9310, which is not inflatable.

In certain forms of the present technology, the patient interfaces 9000,10000, shown in FIGS. 10 and 11, may comprise a connection port 9600located proximal a top, side or rear portion of a patient's head. Forexample, in the forms of the present technology illustrated in FIGS. 10and 11, the connection port 9600 is located on top of the patient'shead. In these examples the patient interfaces 9000, 10000 comprise anelbow 9610 to which the connection port 9600 is provided. The elbow 9610may swivel (e.g., via a swivel ring 9614) with respect to thepositioning and stabilising structure 9300 and order to decouplemovement of a conduit connected to the connection port 9600 from thepositioning and stabilising structure 9300. The elbow 9610 may connectto a fluid connection opening in the headgear tubing 9350 or in acomponent to which the headgear tubing 9350 is connected.

Additionally, or alternatively, a conduit connected to the connectionport 9600 may swivel with respect to the elbow 9610. In the illustratedexample, elbow 9610 comprises a swivelling conduit connector comprisingthe connection port 9600 to which a conduit of the air circuit 4170 isable to connect, such that the conduit can rotate about its longitudinalaxis with respect to the elbow 9610. In some examples the air circuit4170 may connect to the fluid connection opening. The elbow 9610 mayrotatably connect to the fluid connection opening or to a ring receivedin the fluid connection opening.

Patient interfaces in which the connection port is not positioned infront of the patient's face may be advantageous as some patients find aconduit that connects to a patient interface in front of the face to beunsightly and/or obtrusive. For example, a conduit connecting to apatient interface in front of the face may be prone to being tangled upin bedclothes or bed linen, particularly if the conduit extendsdownwardly from the patient interface in use. Forms of the technologywith a patient interface with a connection port positioned proximate thetop of the patient's head in use may make it easier or more comfortablefor a patient to lie or sleep in one or more of the following positions:in a side or lateral position; in a supine position (i.e. on their back,facing generally upwards); and in a prone position (i.e. on their front,facing generally downwards). Moreover, connecting a conduit to the frontof a patient interface may exacerbate a problem known as tube drag,wherein the conduit may provide an undesired drag force upon the patientinterface thereby causing dislodgement away from the face.

In the forms of the present technology illustrated in FIGS. 10 and 11,the positioning and stabilising structure 9300 comprises two tubes 9350,each tube 9350 being positioned in use on a different side of thepatient's head and extending across the respective cheek region, abovethe respective ear (superior to the otobasion superior on the patient'shead) to the elbow 9610 on top of the head of the patient 1000. Thisform of technology may be advantageous because, if a patient sleeps withtheir head on its side and one of the tubes is compressed to block orpartially block the flow of gas along the tube, the other tube remainsopen to supply pressurised gas to the patient. In other examples of thetechnology, the patient interface 9000 may comprise a different numberof tubes, for example one tube, or three or more tubes. In one examplein which the patient interface has one tube 9350, the single tube 9350is positioned on one side of the patient's head in use (e.g. across onecheek region) and a strap forms part of the positioning and stabilisingstructure 9300 and is positioned on the other side of the patient's headin use (e.g. across the other region) to assist in securing the patientinterface 9000 on the patient's head.

In the forms of the technology shown in FIGS. 10 and 11 the two tubes9350 are fluidly connected at their upper ends to each other and toconnection port 9600. In the illustrated examples, the tubes 9350 areseparate tubes that are connected to a crown connector 9360. The tubes9350 are indirectly connected to each other by the crown connector 9360and may be disconnected, for example for cleaning or storage. In anotherexample, the two tubes are integrally formed and comprise a fluidconnection opening to which a swivel elbow connects. In other exampleswhere separate tubes are used they may be indirectly connected together,for example each may be connected to a T-shaped conduit having twoconduit arms each fluidly connectable to the tubes 9350. The crownconnector 9360 may comprise a third conduit arm. The connection port9600 may comprise an elbow 9610 received in fluid connection opening9390 at the centre of the crown connector 9360. The fluid connectionopening may form a sealing flange 9362. The elbow 9610 may be receivedin a ring in the fluid connection opening 9390 and may form a seal witha sealing flange 9362 provided to the ring. The elbow 9610 may beconfigured to swivel within the ring. The fluid connection opening 9390may be also considered a connection port 9600 itself.

The tubes 9350 may be formed from textile, spacer fabric and/or foammaterials, in some examples. In some examples the spacer fabric materialitself comprises layers. The spacer fabric may comprise a textilesandwich structure. The spacer fabric may comprise a face layer, backlayer and an internal spacer layer. The internal spacer layer may beformed by a network of fibres and be relatively open.

Spacer fabric may advantageously be used to provide good cushioning dueto the middle layer being highly compressible and also breathable. Themiddle layer may also be resilient. Spacer fabric may be used in eitherthe patient contacting portion 9348 or the non-patient contactingportion 9349 and may be either an intermediate layer or an outer layer.In other examples, the tubes 9350 may be formed of a semi- rigidmaterial such as an elastomeric material, e.g. silicone. The tubes mayhave a natural, preformed shape although may have at least some abilityto deform if a force is applied to the tubes or conform to a patient'shead. For example, the tubes may be generally arcuate or curved in ashape approximating the contours of a patient's head between the top ofthe head and the nasal or oral region.

The positioning and stabilising structure 9300 in some examples maycomprise sleeves around the tubes 9350. In some examples, the patientinterface 9000 may not comprise sleeves and in other examples thepatient interface 9000 may comprise sleeves that cover more, or all, ofthe tubes 9350. The sleeves may be formed to fit to the curved shape ofthe tubes 9350. In some examples, the sleeves are formed from a smoothfabric. The sleeves may be more comfortable against the patient's facethan the tube 9350 without any covering.

As described in U.S. Pat. No. 6,044,844, the contents of which areincorporated herein, the tubes 9350 may be crush resistant to avoid theflow of breathable gas through the tubes if either is crushed duringuse, for example if it is squashed between a patient's face and pillow.Crush resistant tubes may not be necessary in all cases as thepressurised gas in the tubes may act as a splint to prevent or at leastrestrict crushing of the tubes 9350 during use. A crush resistant tubemay be advantageous where only a single tube 9350 is present as if thesingle tube becomes blocked during use the flow of gas would berestricted and therapy will stop or reduce in efficacy.

In certain forms of the technology, one or more portions of the tubes9350 may be rigidised by one or more rigidising or stiffening elements.Examples of rigidising elements include: sections of the tubes 9350 thatare comparatively thicker than other sections; sections of the tubes9350 that are formed from a material that is comparatively more rigidthat the material forming other sections; and a rigid member attached tothe inside, outside or embedded in a section of tube. The use of suchrigidising elements helps to control how the positioning and stabilisingstructure 9300 will function in use, for example where the tubes 9350 ismore likely to deform if forces are applied to them and where the shapeof the tubes 9350 is more likely to be maintained if forces are applied.The selection of where such rigidising elements are positioned in thetubes 9350 can therefore help to promote comfort when the patientinterface 9000 is worn and can help to maintain a good seal at theseal-forming structure 9100 during use. Rigidising or stiffeningelements may be in positioning and stabilising structures 9300 which areconfigured to support relatively heavy seal-forming structures such asfull face or oro-nasal cushion assemblies.

In certain forms of the technology, one or more portions of the tubes9350 may be formed lengthways from at least two parts, the rigidisingelements being inside, outside or embedded within the intersection ofthe at least two parts.

The tubes 9350 in the form of the technology shown in FIGS. 10 and 11have a length of between 15 and 30 cm each, for example between 20 and27 cm each. The length of the tubes is selected to be appropriate forthe dimensions of the heads of typical patients, for example thedistance between the region proximate the top of the head where theupper end of the tubes 9350 are situated, and the region proximate theopenings to the patient's airways at which the lower end of the tubes9350 connect to the cushion module 9150 when following a generallyarcuate path down the sides of the heads and across the patient's cheekregion (such as the arcuate path taken by the tubes 9350 shown in FIGS.10 and 11). In some examples, the patient interface 9000 may beconfigured so that the length of the tubes 9350 can be varied. It willbe appreciated that the length of the tubes 9350 will depend on thelength of other components in the patient interface 9000, for examplethe length of the crown connector 9360 to which the superior ends of thetubes 9350 connect and/or the size of the plenum chamber 9200.

5.3.3.2.1.1 Positioning of Headgear Components

Each tube 9350 may be configured to receive a flow of air from theconnection port 9600 on top of the patient's head and to deliver theflow of air to the seal-forming structure at the entrance of thepatient's airways. In the examples of FIGS. 10 and 11, the at least onetube 9350 extends between the seal-forming structure 9100 and theconnection port 9600 across the patient's cheek region and above thepatient's ear, i.e. a portion of tube 9350 that connects to the cushionmodule overlays a maxilla region of the patient's head in use and aportion of tube 9350 overlays a region of the patient's head superior tothe otobasion superior on the patient's head. Each of the one or moretubes 9350 may also lie over the patient's sphenoid bone and/or temporalbone and either or both of the patient's frontal bone and parietal bone.The connection port 9600 and elbow 9610 may be located in use over thepatient's parietal bone, frontal bone or the junction therebetween.

The exemplary forms of the technology illustrated in FIGS. 10 and 11 hastubes 9350 which curve around the upper part of the patient's head fromthe upper end of the tubes 9350 that connect to elbow 9610 on top of thehead to the point at which the strap 9310 connects to the tubes 9350with relatively little curvature in the sagittal plane. In between thepoint at which the rear headgear strap 9310 connects to the tubes 9350and the lower ends of the tubes 9350 at which they connect with thecushion module 9150 in front of the patient's airways under the nose,the tubes 9350 curve forwards between the patient's ears and eyes andacross the cheek region. The radius of curvature of this section of thetubes 9350 may be in the range 60-100 mm, for example 70-90 mm, forexample 80 mm. The lower end of the tubes 9350 and the section of thetubes 9350 at which the rear headgear strap 9310 connects to the tubes9350 may subtend an angle in the range 65-90°, for example 75-80°. Theactual curvature present in the portions of the tubes 9350 superior tothe strap 9310, and the actual curvature in the portions of the tubes9350 inferior to the strap 9310, depends on patient setup and inpractice will vary depending on the shape and size of the patient's headand the patient's preferences.

The degree to which the patient interface 9000 fits an individualpatient can be altered by varying the length of the tubes 9350 and,alternatively or additionally, by altering the position of the patientinterface 9000 or portions thereof on the patient's head. For example, apatient interface 9000 having tubes 9350 of a certain length can beadjusted to better fit a patient by moving portions of the positioningand stabilising structure 9300 in the posterior or anterior direction onthe patient's head. For example, positioning the junction of the tubes9350 above the patient's head further forward (i.e. in the anteriordirection) enables a patient interface 9000 having tubes 9350 of acertain length to fit a larger head than if the junction of the tubes9350 is positioned further backward (i.e. in the posterior direction).In most patients, if the junction of the tubes 9350 is positionedforwardly, the superior portions of the tubes 9350 lie over a smallerportion of the patient's head than if the junction of the tubes 9350 ispositioned rearwardly. In some examples of the technology, the tubes9350 are less flexible and the patient may have less freedom to move thesuperior portions of the tubes 9350 anteriorly or posteriorly on theirhead.

In certain forms of the present technology the patient interface 9000 isconfigured such that the connection port 9600 can be positioned in arange of positions across the top of the patient's head so that thepatient interface 9000 can be positioned as appropriate for the comfortor fit of an individual patient. One way this can be achieved so thatthe seal-forming structure 9100 forms an effective seal with thepatient's face irrespective of the position of the connection port 9600on the patient's head is to de-couple movement of the upper portion ofthe patient interface 9000 from the lower portion of the patientinterface 9000. Such de-coupling can be achieved by, for example,forming the tubes 9350 to be sufficiently flexible that the superiorportions of the tubes 9350 can be moved.

In a certain form of the present technology, the patient interface 9000is configured such that the connection port 9600 is positionedapproximately at a top point of the patient's head. The connection port9600 may be positioned in the sagittal plane and aligned with theotobasion superior points in a plane parallel to the coronal plane. Theotobasion superior points are identified in FIG. 2D. In some forms ofthe technology, the positioning and stabilising structure 9300 isconfigured to be worn in different positions, with the effect that theconnection port 9600 may be positioned proximate the top of thepatient's head in the sagittal plane up to around 20 mm forward or 20 mmrearward of the otobasion superior points.

In some examples of the present technology, the connection port 9600 maybe positioned in the sagittal plane and aligned with a junction betweenthe frontal bone and the parietal bones. The connection port 9600 may bepositioned approximately over the junction of the coronal suture and thesagittal suture. In this configuration, the superior portions of thetubes 9350 may lie over and/or along a portion of the coronal suture.However, as mentioned above the patient has the ability to move theconnection port 9600 anteriorly or posteriorly in order to adjust thefit of the patient interface 9000, in some forms of the presenttechnology.

An advantage provided by the tubes 9350 overlying the patient's headslightly anterior to the superior-most point (e.g. at or proximate thecoronal suture) is that the risk of the tubes 9350 riding in a posteriordirection in use may be reduced. In many patients there may be a recessor “divot” where the coronal suture meets the sagittal suture. Thepositioning and stabilising structure 9300 may be particularly stablewhen tubes 9350 lie within this divot. Accordingly, in some examples thetubes 9350 are configured with appropriate curvature and/or ability tocurve in order to lie over the coronal suture.

As described above, in some examples of the present technology thepatient interface 9000 comprises a seal-forming structure 9100 in theform of a cradle cushion which lies generally under the nose and sealsto an inferior periphery of the nose. The positioning and stabilisingstructure 9300 may be structured and arranged to pull the seal-formingstructure 9100 into the patient's face under the nose with a sealingforce vector that has a posterior and superior direction (e.g. aposterosuperior direction). A sealing force vector with aposterosuperior direction may facilitate the seal-forming structure 9100forming a good seal to both the inferior periphery of the patient's noseand the anterior-facing surfaces of the patient's face on either side ofthe patient's nose and the upper lip.

In some examples, the positioning and stabilising structure 9300 may inuse apply a sealing force vector having a posterosuperior direction atan angle of approximately 35° with respect to the patient's Frankforthorizontal (identified in FIG. 2E). The superior portions of the tubes9350 (e.g. the portions of the tubes 9350 superior to the strap 9310)may be oriented vertically, and the rear headgear strap 9310 may extendfrom the tubes 9350 in a posteroinferior direction at an angle ofapproximately 35° with respect to the patient's Frankfort horizontal. Inone example, there is an angle of about 125° formed between the strap9310 and the superior portions of the tubes 9350 where the strap 9310connects to the tubes 9350.

In some examples the positioning and stabilising structure 9300 may beconfigured such that the superior portions of the tubes 9350 lie acrossthe patient's head slightly anterior to a superior-most point. For somepatients this may result in the tubes 9350 being angled slightlyanteriorly rather than aligned vertically (e.g. in the coronal plane) inorder to lie within a slight recess at or proximate the coronal sutureof the skull. In such an example, the tension in the strap 9310 could beadjusted by the patient to balance the forces and achieve the optimalsealing force vector.

In some examples, the positioning and stabilising structure 9300 may beconfigured to apply a force on the seal-forming structure 9100 in aposterosuperior direction at an angle that bisects an angle formedbetween the upper lip and the columella (e.g. the surfaces forming thenasolabial angle).

In certain examples of the present technology, the tubes 9350 areconfigured to receive the strap 9310 at the locations superior to andproximate the patient's ears. If the strap 9310 connects to the tubes9350 too high with respect to the patient's head, the strap 9310 mayhave a tendency to ride up the back of the patient's head. Additionally,the strap 9310 could form too large of an angle with respect to thesuperior portions of the headgear tubes 9350, resulting in the necessityfor the patient to tighten the strap 9310 excessively, which couldresult in both excessive tension in the positioning and stabilisingstructure 9300 and make the strap 9310 more likely to ride up the backof the patient's head. Accordingly, it is advantageous for theconnection between the strap 9310 and the tubes 9350 to be provided aslow as possible but spaced from the top of the patient's earsufficiently that upon tightening of the strap 9310, the tubes 9350 arenot pulled into contact with the patient's ears.

5.3.3.2.1.2 Headgear Tube Fluid Connections

The two tubes 9350 are fluidly connected at their inferior ends to theplenum chamber 9200. In the examples of FIGS. 10 and 11, the tubes 9350form a fluid connection with the cushion module 9150 and seal-formingstructure 9100. In certain forms of the technology, the connectionbetween the tubes 9350 and the cushion module 9150 is achieved byconnection of two rigid components so that the patient can easilyconnect the two components together in a reliable manner. The tactilefeedback of a ‘re-assuring click’ or like sound may be easy for apatient to use or for a patient to know that the tube has been correctlyconnected to the cushion module 9150. In one form, the tubes 9350 areformed from textile and foam materials and the lower end of each of thetubes 9350 is overmolded or bonded to a rigid connector made, forexample, from polypropylene, polycarbonate, nylon or the like. The rigidconnector may comprise a male mating feature configured to connect to afemale mating feature on the cushion module 9150. Alternatively, therigid connector may comprise a female mating feature configured toconnect to a male mating feature on the cushion module 9150. The samemanner of connection by which the tubes 9350 are connected to thecushion module 9150 may also be applied to the connection between thetubes 9350 and another plenum chamber 9200 or seal-forming structure9100, such as a nasal pillows cushion module.

In a hard-to-hard type engagement between the tube 9350 and port, apressure activated seal such as a peripheral sealing flange may be used.When pressurised gas is supplied through the tubes 9350 the sealingflange is urged against the join between the tubes and the innercircumferential surface of the port of the plenum chamber 9200 toenhance the seal between them. If the port is soft and a rigid connectoris provided to the tube 9350, the pressure activated seal as describedearlier may also be used to ensure the connection is air-tight.

Similar connection mechanisms may be used to fluidly connect the tubes9350 with the crown connector 9360 to which the connection port 9600 isfluidly attached in some forms of the technology. In one embodiment, aswivel elbow connected at the connection port 9600 is rotatable in orderto drive a port size adjustment mechanism that decreases or increasesthe size of the ports into which tubes 9350 are inserted in order toimprove the fit of the tubes through an increase or decrease ofcompressive forces and to reduce unintended leakage.

5.3.3.2.1.3 Extendable Concertina Structure

The patient interface 9000 may comprise one or more extendable tubesections. In some examples, an extendable tube section comprises anextendable concertina structure. The patient interface 9000 may comprisea positioning and stabilising structure 9300 including at least one gasdelivery tube comprising a tube wall having an extendable concertinastructure.

5.3.3.2.1.4 Bendability

In some examples of the present technology, portions of the positioningand stabilising structure 9300 are configured to be more resistant tobending in or about some directions or axes than in or about others.

For example, a superior portion of each tube 9350 of the positioning andstabilising structures 9300 shown in FIGS. 10 and 11 may be morebendable in a particular direction in comparison to an orthogonaldirection. Each gas delivery tube 9350 of the positioning andstabilising structure 9300 may comprise a superior tube portion 9304configured to overlie a superior region of the patient's head in use. Insome examples of the present technology, the superior tube portion 9304may comprise an extendable tube structure (such as one of the optionsdisclosed in PCT Patent Publication No. WO 2017/124155 or in US PatentApplication No. 62/764,995), the entire contents of each of which areincorporated herein by reference) or may be non-extendable. In theillustrated forms of the technology shown in FIGS. 10 and 11, the tubesare substantially non-extendable, save for any inherent stretchabilityin the material(s) forming the tube.

The superior tube portion 9304 comprises a first end 9305 and a secondend 9306. In this example the first end 9305 is configured to overlie orlie against a superior portion of the patient's head, at approximatelysagittal plane of the patient's head (e.g. approximately top and centreof the patient's head). The second end 9306 is configured to overlie thepatient's head laterally from the first end 9305 (e.g. closer to theside of the patient's head). The second end 9306 may lie both laterallyand inferiorly to the first end 9305. The positioning and stabilisingstructures 9300 of FIGS. 10 and 11 are able to bend about multiple axesto at least some extent. For example, the superior tube portion 9304 ofthe positioning and stabilising structure 9300 may be able to drape downover the patient's head and also curve in the anterior and posteriordirections.

In some examples of the present technology, the superior tube portion9304 may also comprise one or more stiffened portions between the firstend 9305 and the second end 9306. The stiffened portion(s) may beconfigured to provide a higher resistance to relative movement betweenthe first end 9305 and a second end 9306 in an anterior and/or posteriordirection than in a superior and/or inferior direction. The stiffenedportions may in some examples be provided to the entire length of thetube 9350, and in some examples may provide varying stiffnesses to thetube 9350 along the length of the tube 9350.

When the patient dons the positioning and stabilising structure 9300,the superior tube portion 9304 may have a relatively low resistance tobending in the vertical directions such that the second end 9306 is ableto move inferiorly with respect to the first end 9305. Thisadvantageously enables the superior tube portion 9304 to “drape”downwardly over the top of the patient's head to the side of thepatient's head. Bendability in the superior/inferior directions may beadvantageous in enabling the superior tube portion 9304 to conform tothe curvature of the patient's head.

Additionally, the superior tube portion 9304 may have a relativelyhigher resistance to bending in the horizontal directions such that thefirst end 9305 does not unintentionally move anteriorly and/orposteriorly with respect to the second end 9306. This advantageouslyenables the superior tube portion 9304 to remain in a desired positionacross the top of the patient's head. With a lower resistance to bendingtowards the anterior and/or posterior directions, the superior tubeportion 9304, and in particular the connection port 9600, may be lesslikely to ride forward or backward along the top of the patient's headin use. This resistance to a forward or backward movement of thesuperior tube portion 9304 is particularly advantageous for the patientinterface 9000 given the connection to the air circuit 4170 is providedatop the patient's head, meaning tube drag forces may act directly onthe superior tube portion 9304.

In some examples, the superior tube portion 9304 may comprise a shapewhich inherently provides the advantageous resistance to bending. Forexample, the superior tube portion 9304 may comprise a somewhatrectangular or trapezoidal cross-section with the parallel long sidesconfigured to lie against the surfaces of the patient's head. The longsides of the rectangular cross section provide a relatively largeresistance to bending of the superior tube portion in directionsparallel to the long sides (e.g. the anterior and/or posteriordirections in use). However, the short sides of therectangular/trapezoidal cross section may not provide such a largeresistance to bending of the superior tube portion 9304 and directionsparallel to the short sides (e.g. the inferior and/or superiordirections in use).

It will be appreciated that the cross-section of the superior tubeportion 9304 may not be perfectly rectangular. For example, the cornersand/or short sides may be rounded such that the cross-section of thesuperior tube portion 9304 may be substantially oval or elliptical.However, a cross-sectional shape that presents a flattened surface oftube on the side that faces and contacts the patient's face or otherpart of the head may be more comfortable to wear than, for example atube with a circular cross-section.

The stiffened portion may be formed by one or more rigidising structuresformed by or provided to the tube wall of the tube 9350. A tube 9350that comprises stiffened portions on both the anterior and posteriorsides of the tube 9350 may advantageously have a higher resistance tobending towards both the anterior and posterior sides of the tube 9350.However, in some examples a stiffened portion is provided to only one ofthe anterior or posterior sides of the tube 9350 since, depending on thestiffness, a stiffened portion on one side only may provide a sufficientresistance to bending towards both directions.

In some examples, portions of the tubes 9350 (e.g. anterior and/orposterior portions) may comprise stiffened portions being stiffened withone or more rigidising elements. The tubes 9350 may be rigidised withone or more rigidising components having a higher stiffness than thetube 9350 embedded within the tube wall. For example, the tube wall maybe bonded to an elongate bar or rod formed from a material stiffer thanthe tube wall. In other examples, a stiffened portion of the tube wallmay be provided by further features of the geometry of the tube wall. Inone example the tube wall may comprise a greater material thickness atthe anterior and/or posterior sides of the tube 9350.

5.3.3.2.1.5 Inferior Tube Portions

The patient interface 9000 may comprise one or more inferior tubeportions 9363. For example, the patient interfaces 9000 shown in FIGS.10 and 11 comprise tubes 9350, the inferior portions of which compriseinferior tube portions 9363. The inferior tube portions 9363 areconfigured to overlie the patient's cheeks and may be configured tocontact the patient's face inferior to the patient's cheekbones. Eachinferior tube portion 9363 may lie on a curve extending inferiorly fromthe connection between the respective headgear tube 9350 and thenextending in a partially anterior and partially medial direction towardsthe seal-forming structure 9100 in order to avoid the patient's cheekbones.

It is advantageous that the positioning and stabilising structure to9300 of the patient interface 9000 does not lie over the patient's cheekbones. The regions of a patient's face inferior to the cheekbones aregenerally more fleshy and a patient may find it more tolerable for theheadgear tubes 9350 to lie over these regions of the face. Additionally,since the cheek bone regions of the patient's face are relatively unableto move or deform, the inferior tube portions 9363 lie firmly againstthe fleshy cheek regions. Further, the patient's cheek bones can assistin preventing the inferior tube portions 9363 of the headgear tubes 9350from riding up over the cheekbones towards the patient's eyes. When theinferior tube portions 9363 fit snugly against the patient's cheeksbelow the cheekbones, the hardness and prominence of the patient'scheekbones may provide a barrier to the headgear tubes 9350 riding uptowards the patient's eyes (which could affect stability and/or mayobscure the patient's vision).

The cross-sectional shape of the inferior tube portions 9363 of thetubes 9350 may be circular, elliptical, oval, D-shaped, trapezoidal or arounded rectangle, for example as described in U.S. Pat. No. 6,044,844.A cross-sectional shape that presents a flattened surface of tube on theside that faces and contacts the patient's face or other part of thehead may be more comfortable to wear than, for example a tube with acircular cross-section.

The cross-sectional width and/or height of the tubes 9350 may be in therange 8-35 mm. In some forms in which the tubes have an approximatelyD-shaped cross-section, the tubes may have a width in the range 15-25mm, and a height in the range 6-15 mm. The height may be considered tobe the dimension of the tube extending away from the patient's face inuse, i.e. the distance between a patient contacting portion 9348 and theoutermost part of a non-patient contacting portion 9349, while the widthmay be considered to be the dimension across the surface of thepatient's head. The cross-sectional thickness of the material formingthe tubes 9350 may be in the range 0.8-1.6 mm, for example 1.0-1.5 mm.

A further advantage of the rectangular-shaped cross section of theinferior tube portions 9363 of the tubes 9350 is that the inferior tubeportions 9363 that lie in front of the patient's face in use are moreresistant to bending in the vertical directions than in the horizontaldirections. The D-shaped cross-section makes the inferior tube portions9363 more resistant to bending parallel to the long axis of therectangle/trapezoid than to bending perpendicular to the long axis ofthe rectangle/trapezoid. This is advantageous as the inferior tubeportions 9363 are more readily able to bend to curve inwardly around thefront of the patient's face to the seal-forming structure 9100, yetretain stiffness in the vertical direction to enable the vertical forcesapplied on the inferior tube portion 9363 from the superior tubeportions 9304 to be transferred to the seal-forming structure 9100 inorder to provide the necessary sealing force to the seal-formingstructure 9100.

The ability to bend inwardly around the front of the patient's faceenables the inferior tube portions 9363 to fit snugly against thepatient's cheeks inferior to the patient's cheekbones. As describedabove in more detail, inferior tube portions 9363 that lie snugly underthe patient's cheekbones may provide for a more stable seal thaninferior tube portions 9363 that lie loosely over the patient's cheeksor lie high over the patient's cheekbones.

In some examples of the present technology, the inferior tube portions9363 connect to a cushion module 9150 from a low angle. As describedabove, the headgear tubes 9350 may extend laterally and inferiorly downthe sides of the patient's head and then curve anteriorly and mediallyto connect to a cushion module 9150 in front of the patient's face. Thetubes 9350, before connecting to the cushion module 9150, may extend toa location at the same vertical position as or, in some examples,inferior to the connection with the cushion module 9150. That is, thetubes 9350 may project in an at least partially superior directionbefore connecting with the cushion module 9150. A portion of the tubes9350 may be located inferior to the cushion module 9150 and/or theseal-forming structure 9100. The low position of the tubes 9350 in frontof the patient's face facilitates contact with the patient's face belowthe patient's cheekbones.

5.3.3.2.1.6 Conduit Headgear Materials

In some examples of the present technology, such as the examples shownin FIGS. 10 and 11, the headgear tubes 9350 are formed at leastpartially from a textile material. In some examples, the textilematerial comprises nylon. In other examples, the textile materialcomprises polyester. The textile material may comprise other suitablematerials and may comprise a combination of materials, for example woventogether. Additionally or alternatively, the tubes 9350 may be formedfrom a foam material. In some examples the tubes 9350 comprise acombination of textile and foam materials. In some examples the tubes9350 comprise a spacer fabric material.

In some examples the textile and/or foam is in addition to the use ofsilicone. The seal forming structure 9100 may be formed from silicone.The plenum chamber 9200 may also comprise a rigid material such aspolycarbonate.

In examples, headgear tubes 9350 comprising textile and/or foammaterials may: hold air under pressure, be biocompatible andsuitable/approved for use in forming a medical air path, be lighter thansilicone tubes, be soft and flexible, generally retain a predeterminedshape, be cleanable and be durable for a predetermined lifecycle such asa one month, three months, six months, a year or longer.

In examples, the headgear tubes 9350 of the patient interfaces 9000shown in FIGS. 10 and 11 may comprise a film barrier to prevent entry ofunwanted matter into the air path, comprise a film that provides somestructure positioning and stabilising structure 9300, be at leastsomewhat elastically extendable, comprise a low weight (in some examplesless than 30g), have a low wall thickness (in some examples less than 1mm), have low acoustic resonance, in some examples be formed completelyfrom textiles, have a sufficiently low impedance to flow/pressure, besufficiently stable, have a seam that may provide rigidity to the tubes9350, have a seam that varies along the length of the tubes 9350 toprovide different rigidities to different parts of the tube 9350, maycomprise asymmetrical seams across the posterior and anterior sides ofthe tubes 9350, may comprise a flat portion of the tube 9350 on thepatient-contacting side which is under tension in use, may bethermoformed, may have a thermoformed seam, may comprise one or moretextile spacers, may be assembled with a crown connector 9360 havingdifferent properties than the tubes 9350, may have a soft feel on thepatient's face, may be highly breathable, may be washable and/or mayhave similar look and feel to bedclothes and/or a pillow.

As shown in FIGS. 10 and 11, a crown connector 9360 connects betweeneach of the headgear tubes 9350 of the patient interface 9000. The crownconnector 9360 may comprise the swivel elbow 9610 and a connection port9600. The connection port 9600 may be provided by the conduit connector9612 which is configured to connect to an air delivery conduit, such asair circuit 4170) that provides a supply of breathable gas. The conduitconnector 9612 may be rotatable relative to the elbow so as to allow theair delivery conduit to rotate relative to the elbow. The crownconnector 9360 is shown together with the swivel elbow 9610 in FIG. 24,and shown in isolation in FIG. 25. In the examples shown in FIGS. 10, 11and 20-23 the headgear tubes 9350 removably connect to the crownconnector tube portions 9365 of the crown connector 9360. The headgeartubes 9350 may comprise male connectors at their ends. As shown in FIGS.12A, 12B and 26, each headgear tube 9350 comprises a headgear tubeconnector 9351 at each end. The headgear tube connectors 9351 mayrespectively form a snap fit connection to a corresponding femaleconnector portions in the crown connector ports 9361 of the crownconnector 9360 and the cushion module 9150. Each of the headgear tubes9350 may comprise a seal portion 9353 proximate each connector 9351 (asshown in FIGS. 12A and 12B). The seal portions 9353 may be formed from acompliant material (e.g. silicone) to form a good seal to the crownconnector 9360 and cushion module 9150. The crown connector 9360 andcushion module 9150 may be formed from a resilient material such assilicone as well, or a harder material such as polycarbonate,polypropylene, nylon or the like.

In one example, the headgear tubes 9350 have a lifespan of nine months.They may be machine washable at home designed to withstand 40 to 100cleaning cycles at 70° C. for 30 minutes, or 30 cleaning cycles at 93°C. for 10 minutes.

In addition to a possible comfort advantage of using a textile materialin headgear conduits such as the headgear tubes 9350, a headgear tube9350 formed using textile material may be able to be made significantlylighter than would be possible using silicone. In some examples theconduit headgear may have a weight that is less than 30 grams. A lightersystem is generally more desirable as the patient's head does not needto support as much weight, improving patient comfort. A textile conduitpatient interface 9000 may be lighter due to the density of the textilematerial being lesser than the density of silicone and/or due to theconduits being able to be formed with thinner walls than would beachievable using silicone. In some examples the walls of the headgeartubes 9350 may have a thickness that is less than 1 mm.

5.3.3.2.1.7 Conduit Rigidity

The headgear tubes 9350 may advantageously be soft and deformable forcomfort but may also be stable when in use. The headgear tubes 9350 maybe configured to apply appropriate force vectors to the plenum chamber9200 to achieve an effective, comfortable and stable seal between theseal-forming structure 9100 and the patient's face. Additionally, eachheadgear tube 9350 may follow a curved path on the patient's headlaterally away from the connection port 9600 atop the patient's head,inferiorly down the side of the patient's head and anteriorly towardsthe patient's nose. This shape enables each headgear tube 9350 to passbetween the patient's eye and ear while conveying gas from the swivelelbow atop the patient's head to the cushion at the patient's nose. Thismeans that some rigidity in the headgear tubes 9350 is advantageous sothat they retain their shape while converting tension in the headgeartubes 9350 and strap 9310 into the necessary force vectors for a goodseal.

The headgear tubes 9350 may be configured to: provide the function ofheadgear, be more rigid in some places than others, be more flexible insome places than others (e.g. more, or less, stretchy and/or flexible),and/or be bendable. U.S. Patent Application No. 62/764,995 (the entirecontents of which are incorporated herein by reference) discloses anumber of ways in which a headgear tube may be configured to bend andbehave.

The superior tube portions 9304 of the headgear tubes 9350 may besufficiently bendable to “drape” down over the superior surfaces of thepatient's head, yet have sufficient stiffness to resist movement in theanterior-posterior directions to resist riding backwards or forwards onthe patient's head. The inferior tube portions 9363 of the headgeartubes 9350 may be sufficiently bendable to wrap around the patient'shead in a medial direction from the lateral sides of the patient's headtowards the plenum chamber 9200 located under the patient's nose.However, the inferior portions 9363 must retain sufficient rigidity(especially to bending in the superior- inferior directions) to convertand transmit tension in the superior tube portions 9304 of the headgeartubes 9350 and the headgear backstrap 9310 into sealing force vectorsapplied to the seal forming structure 9100.

The headgear tubes 9350 may be formed from a combination of textilesand/or foam materials yet may have a flexibility similar to headgeartubes 9350 formed from silicone. An appropriate flexibility is importantfor both stability and comfort.

The textile headgear tubes 9350 may have a predetermined rest shape thatapproximates the shape that they will have in use when worn by a patient(e.g. the general shape shown in FIGS. 10, 11 and 20-23). However, theheadgear tubes 9350 may be sufficiently flexible to conform comfortablyand securely to the actual shape of the patient's head.

The textile headgear tubes 9350 may be configured to resist torsionalforces. This is particularly advantageous because the headgear tubes9350 are formed in a three-dimensional loop and receive forces that arenonparallel to the three-dimensional curve along which the headgeartubes 9350 lie.

In some examples, the headgear tubes 9350 themselves are constructed toprovide the necessary level of rigidity. In one example, the rigidity isprovided to the tubes 9350 by their cross-sectional shape. For example,the cross sectional shape of each headgear tube 9350 may comprise asufficiently large second moment of area to provide structuralstiffness. In some examples, the properties of the materials used toform the tubes 9350 may provide sufficient stiffness to the tubes 9350.For example, the materials may be substantially inextensible and/or thematerial used may comprise a sufficiently large stiffness. In someexamples, the manner in which the materials are assembled may providestiffness, and/or the processing of the materials (e.g. thermoforming)during or prior to assembly may provide sufficient stiffness to theheadgear tubes 9350. In one example, the textile tubes 9350 areconstructed from a foam material thermoformed into a predeterminedshape, which imparts the necessary rigidity.

In one example, the laterally outward, non-patient contacting side ofthe tube 9350 may be configured to stretch to allow the tube 9350 tobend such that it curves inwardly (e.g. in a medial direction from alateral side of the patient's head around in front of the patient's faceto approach the patient's nose and/or mouth). The patient contactingside may not stretch (or may stretch to a lesser extent). Thepatient-contacting portion 9348 of the headgear tube 9350 may comprise agreater stiffness, or at least be less stretchable, than thenon-patient-contacting portion 9349 of the headgear tube 9350 to enablethis difference in stretch in use.

There are a number of ways in which the patient-contacting portion 9348of each of the headgear tubes 9350 can be made more rigid than thenon-patient-contacting portion 9349. In one example, thepatient-contacting portion 9348 may be formed from a stiffer materialthan the non-patient contacting portion 9349. In other examples, thepatient-contacting portion 9348 may be thicker than thenon-patient-contacting portion 9349, may be thermoformed in a way thatresults in less stretchiness and/or a greater rigidity/stiffness thanthe non-patient contacting portion 9349, may be laminated with an extralayer of material that is not applied to the non-patient-contactingportion 9349, may be laminated with a stiffer layer of material than anylayers that are provided to the non-patient-contacting portion 9349, mayinclude a rigidising member and/or may include a textile material thatis formed using a different weaving process that is less flexible orstretchable than the weaving process used on the non-patient-contactingportion.

In one example, the patient contacting portion 9348 may be formed by afirst thermoforming process and the non-patient contacting portion 9349may be formed by a second thermoforming process. The first thermoformingprocess may provide a greater rigidity to the patient contacting portion9348 than the second thermoforming process provides to the non-patientcontacting portion 9349.

In some examples, the patient contacting portion 9348 and thenon-patient contacting portion 9349 are each formed by layers. Thepatient contacting portion 9348 may comprise a greater number of layersthan the non-patient contacting portion 9349, resulting in a higherstiffness than the non-patient contacting portion 9349. In someexamples, the patient contacting portion 9348 comprises a rigidisinglayer and/or a rigidising member.

The non-patient-contacting portion 9349 may also be formed in a shapethat lends itself to greater stretchiness and/or lower rigidity than thepatient-contacting portion 9348 (e.g. a shape in which the material isnot taut). The non-patient-contacting portion 9349 could also be formedto have a concertina or bellows structure that enables the material tounfold to facilitate a change in length.

As described above, the headgear tubes 9350 may be formed in portions:an elongate patient-contacting portion 9348 and an elongatenon-patient-contacting portion 9349.

In one example, the wall of each headgear tube 9350 comprises at leastone seam 9352 formed by an edge of the non-patient contacting portion9349 being joined to a respective edge of the patient contacting portion9348. FIG. 27 shows a cross section of the headgear tube 9350 at asuperior tube portion 9304 (e.g. the portion that lies against superiorsurfaces of the patient's head in use) and FIG. 28 shows a cross sectionof the headgear tube 9350 at an inferior tube portion 9363 (e.g. theportion that lies against lateral and anterior surfaces of the patient'shead in use).

As shown in FIGS. 13-15 and 27-29, the patient contacting portion 9348and non-patient contacting portion 9349 of the headgear tubes 9350 arein some examples connected together along both sides, creating a seam9352 along each side. This creates two seams 9352 along the length ofthe tube 9350 on opposing sides of the tube 9350. In use, there may bean anterior seam 9352 that runs along an anterior side of the tube 9350and a posterior seam 9352 that runs along a posterior side of the tube9350. The joint at the seams 9352 preferably does not contact thepatient's skin in use, as this may cause marking and/or discomfort.However, in some examples, the portion of the seam 9352 formed by thepatient-contacting portion 9348 may lie on the patient's head and/orface.

The patient contacting portion 9348 and the non-patient contactingportion 9349 may each comprise an anterior edge and a posterior edge.The anterior edges may be joined along the length of the tube 9350.Similarly, the posterior edges may be joined along the length of thetube 9350. As shown in FIGS. 27 and 28, the anterior edges are in someexamples joined to form an anterior seam 9352 of the tube 9350.

Similarly, the posterior edges are in some examples joined to form aposterior seam of the tube 9350. The anterior seam 9352 and/or theposterior seam 9352 may be thermoformed.

In some examples of the present technology, the seam 9352 may providerigidity to the conduit. The rigidity of the seam 9352 may contribute tothe overall rigidity and behaviour of the tube 9350 and may be selectedto achieve tubes 9350 that form a stable positioning and stabilisingstructure 9300. The rigidity of the seam 9352 may also contribute to theability of the positioning and stabilising structure 9300 to apply thenecessary force vectors to the seal forming structure 9100 for acomfortable, effective and stable seal. An advantage of using the seam9352 to provide the necessary rigidity is that a tube 9350 having atwo-part construction (e.g. a patient-contacting portion 9348 and anon-patient-contacting portion 9349) may necessarily have a seamregardless of whether extra rigidity is required, meaning the seam 9352and/or the seam forming process can be used to increase rigidity withoutadding additional parts or applying additional processes, which couldhave a detrimental effect on comfort and/or cost.

The rigidity provided to the tubes 9350 by the seams 9352 may bepredetermined by selecting a particular thickness for the seams 9352.The thickness of the material forming each of the patient-contactingportion 9348 and non-patient contacting portion 9349 may define, oreffect, the resulting thickness of the seams 9352. The materialthickness of each of the patient contacting portion 9348 and non-patientcontacting portion 9349 in the regions of the seams 9349 may be selectedto achieve a particular seam thickness. For example, thepatient-contacting portion 9348 and the non-patient-contacting portion9349 of a headgear tube 9350 may be formed with thicker or thinner sideedges to achieve a thicker or thinner seam 9350 once the portions arejoined along the edges to form the tube 9350.

The seams 9352 may be thermoformed or formed by ultrasonic welding. Infurther examples, the seams 9352 may be formed by gluing, stitching,over moulding, welding or any other suitable process.

The thermoforming process may affect the stiffness of the seams 9352.For example, a seam 9352 may be compressed to a greater extent duringthermoforming to result in a stiffer seam. For example, a seam 9352formed by a thermoforming process may comprise rigidity provided bycompression of the edges forming the seam 9352 during the thermoformingprocess.

In some examples, the seam 9352 is more rigid in some locations than inother locations. For example, the portion of a headgear tube 9350between the plenum chamber 9200 and the portion of the headgear tube9350 proximate the connection of the strap 9310 may be more rigid thanthe portion of that same headgear tube 9350 between the portion of theheadgear tube 9350 proximate the connection of the strap 9310 and theconnection to a supply tube atop the patient's head. In some examples,the seam 9352 is thicker in a particular region and/or the materialforming the seam 9352 is compressed to a greater extent in a particularregion to make the seam 9352 stiffer in that region. The seam 9352 maycomprise a greater stiffness and/or thickness in the inferior tubeportion 9363 than in the superior tube portion 9304. In some examples,the seam 9352 comprises a greater width in the inferior tube portion9363 of the headgear tube 9350 than in the superior tube portion 9304.

The seams 9352 may also be formed to stiffen the headgear tubes 9350 atother locations, such as proximate the supply conduit connector atop thepatient's head, the backstrap 9310 connections/eyelets and/or theconnections to the plenum chamber 9200.

The seam 9352 may also be used to form the tabs 9320. The tabs 9320 mayprovide eyelets to which a backstrap 9310 can be connected. Aparticularly large seam 9352 may be provided at the location where abackstrap 9310 is to connect, and a hole may be provided in the seam9352 through which the backstrap 9310 can be looped. Alternatively, theeyelet could be formed by only one of either the patient-contactingportion 9348 or non-patient contacting portion 9349 of the headgeartubes 9350. FIG. 30 shows the tab 9320 of a headgear tube 9350 accordingto one example of the technology. The headgear tube 9350 comprises apatient-contacting portion 9348 and a non-patient-contacting portion9349 joined at the edges to form seams 9352. The posterior seam 9352 isshown in FIG. 29. As shown, the tab is formed by a widening of the seam9352. That is, the posterior seam 9352 comprises a widened portion, thewidened portion configured to connect with a strap 9310 of thepositioning and stabilising structure 9300. In this example, theheadgear tube 9350 comprises an extension of the seam 9352 forming thetab 9322. In other examples of the present technology only one of thepatient-contacting portion 9348 and the non-patient-contacting portion9349 extends posteriorly away from the tube wall of the headgear tube9350 to form a tab 9320.

The headgear tube 9350 comprises an eyelet configured to receive a strap9310. More specifically, the posterior seam 9352 comprises the eyelet.The eyelet may comprise a hole configured to receive the strap 9310, thehole allowing the strap to be passed therethrough and looped back andsecured onto itself in the manner shown in FIG. 10.

In this example, the eyelet is in the form of a slit 9322. The slit 9322is formed in the tab 9320 is also shown in FIG. 30. The tab 9320comprises an aperture forming the slit 9322. As shown in FIG. 30 theslit 9322 is elongate and appropriately sized to receive the strap 9310,which as shown in FIGS. 10 and 11 may be a flat strap (e.g. it may bewider than it is thick).

In the example of FIG. 30, the headgear tube 9350 comprises an eyeletrigidiser portion 9324 configured to reinforce the eyelet. The eyeletrigidiser portion 9324 may be formed from a material more rigid than thematerial from which the headgear tube 9350 is formed. In one example theeyelet rigidiser portion 9324 is formed from a substantially rigidplastics material. The eyelet rigidiser portion 9324 may be formed fromnylon, polycarbonate, Hytrel, polypropylene, or the like. The eyeletrigidiser portion 9324 may be provided to an opening in the tab 9320 andhave a hole therein to form the slit 9322. The eyelet rigidising portion9324 may be provided within the hole in the posterior seam 9352 and maybe configured to reinforce the shape of the hole. The eyelet rigidiserportion 9324 may reinforce the slit and or distribute the force on thetab 9320 from the strap 9310 over a sufficiently large area of the tab9320. The eyelet rigidiser portion 9324 may be permanently connected tothe tab 9320, for example by overmoulding or gluing, or may be removablyattached in the manner of a grommet.

In the positioning and stabilising structure 9300 shown in FIG. 11, theeyelet rigidiser portion 9324 is provided to peripheral edges of thematerial of the headgear tube 9350 forming the tab 9320 and comprises aslit 9322 located posteriorly to the material of the headgear tube 9350forming the tab 9320. In this example, the eyelet rigidiser portion 9324distributes the force of the strap 9310 over a large area of the tab9320.

In further examples, the headgear tubes 9350 may comprise adjustabletabs 9320. That is, the position and/or angle of the tabs 9320 may beadjustable by the patient, either through a continuous range or throughdiscrete options. U.S. Patent Application No. 62/764,995 (the entirecontents of which are incorporated herein by reference) discloses anumber of features relating to adjustable eyelets/tabs for headgeartubes which are applied to the tabs 9320 of the headgear tubes 9350 insome examples of the present technology.

Additionally, or alternatively, different seams 9352 of a textileconduit mask may have different rigidities. For example, the seam 9352on the superior or anterior side of a textile headgear tube 9350 may bemore rigid than the opposing seam 9352 on the inferior or posterior sideof the same textile headgear tube 9350. Alternatively, the inferior orposterior seam 9352 may be stiffer than the superior or anterior seam9352. Where a headgear tube 9350 comprises an anterior seam 9352 and aposterior seam 9352, a greater rigidity can be provided to the anteriorseam 9352 by a greater compression during a thermoforming process of theedges forming the anterior seam 9352 than of the edges forming theposterior seam 9352.

In some examples, the anterior seam 9352 comprises a greater thicknessthan the posterior seam 9352. The anterior seam 9352 may, additionallyor alternatively, comprise a greater width than the posterior seam 9352.

In some examples, the seam 9352 may be positioned away from the skinand/or may be formed with rounded edges to prevent edge marking ordiscomfort caused by the seam 9352 on the patient's face.

Alternative examples of the technology may comprise forming the seam9352 by stitching, moulding to shape, 3D printing, gluing, overmoulding,ultrasonic welding, among other processes.

5.3.3.2.1.8 Two Part Construction

In one example, a headgear tube 9350 is provided which can both hold itscross-sectional shape and conform to the patient's head.

The headgear tube 9350 comprise a patient contacting portion 9348 andnon-patient contacting portion 9349. The patient contacting portion 9348and the non-patient contacting portion 9349 may comprise sufficientrigidity to maintain a hollow interior (i.e. open passage) therebetweenyet be sufficiently flexible and/or stretchable to enable the tube 9350to conform to a patient's head while providing the necessary functionsof the positioning and stabilising structure 9300, e.g. supporting aseal forming structure 9100 in the correct position for an effective,stable and comfortable seal in use.

FIGS. 13-17 and 26-28 show examples of the construction of headgeartubes 9350. The use of a patient contacting portion 9348 (also known asa face contacting portion 9348) and a non-patient contacting portion9349 (also known as a non-face contacting portion 9349) may enable awider range of different properties than may be possible if the entireheadgear tube 9350 is an integrally formed part.

Each of the patient contacting portion 9348 and the non-patientcontacting portion 9349 comprises an elongate length of material (or alength formed by a plurality of layered materials). The two lengths maybe joined along their long edges to form a headgear tube 9350 in theform of an elongate conduit. As shown in FIG. 15, each of the patientcontacting portion 9348 and non-patient contacting portion 9349 maycomprise an anterior edge 9331 and a posterior edge 9332. It will beunderstood that, since the tubes 9350 comprise curvature in threedimensions, the anterior edge 9331 and posterior edge 9332 may not pointdirectly anteriorly and posteriorly, respectively, in use. For example,the anterior edge 9331 may face substantially anteriorly in useproximate the superior end of the headgear tube 9350 but may facepartially anteriorly and partially superiorly in use proximate theinferior end of the headgear tube 9350. Similarly, the posterior edge9332 may face substantially posteriorly in use proximate the superiorend of the headgear tube 9350 but may face partially posteriorly andpartially inferiorly in use proximate the inferior end of the headgeartube 9350. Overall, the anterior edge 9331 may be the more anterior edgein use and the posterior edge 9332 may be the more posterior edge inuse. The anterior edges 9331 and posterior edges 9332 may be joinedalong the length of the gas delivery tube 9350.

In one example the patient contacting portion 9348 may pull thenon-patient contacting portion 9349 into a curved shape to create aD-shaped cross-section within the headgear conduit. The patientcontacting portion 9348 may be in tension pulling the non-patientcontacting portion 9349 into the curved shape. The non-patientcontacting portion 9349 may be biased towards a flat, or flatter, shape.

FIG. 29 shows a cross section view of a headgear tube 9350 formed by apatient-contacting portion 9348 and non-patient contacting portion 9349being joined along the long edges thereof to form a hollow interior toconvey a flow of pressurised gas. The non-patient contacting portion9349 may be biased towards a flat shape. In this example, thenon-patient contacting portion 9349 is biased towards a flat or flattershape than the shape that the non-patient contacting portion 9349 isshown to have in FIG. 29. A bias towards a flat shape will be understoodto refer to a bias into a flatter shape. For example, a non-patientcontacting portion 9349 of a headgear tube 9350 may be biased towards aflat shape, even if its rest shape, in the absence of force from thepatient-contacting portion 9348 acting against the bias, is a flattershape but not a perfectly flat shape. The bias is represented by thecharacter B in FIG. 29. Due to the bias B, the non-patient contactingportion 9349 has a tendency to return to a flat or flatterconfiguration. In this example, the non-patient contacting portion 9349is pulled by the patient contacting portion into a predetermined shapecreating the hollow interior of the tube 9350.

In this example, the predetermined shape is a non-flat shape. Thepredetermined shape approximates a trapezoid in one example. As shown inFIG. 29, the cross sectional shape of the headgear tube 9350 issubstantially trapezoidal and may not be a perfect trapezoid. Forexample, in the FIG. 29 example, the non-patient contacting portion 9349comprises a curved profile along the side between the two angled sides.Additionally, the corners of the cross sectional shape are rounded.

The patient contacting portion 9348 may also comprise a non-flat shape.As shown in FIG. 29, the patient contacting portion 9348 comprises aflatter shape than the non-patient contacting portion 9349.

The non-patient contacting portion 9349 may be deformed, at leastpartially elastically, during joining of the edges of the non-patientcontacting portion 9349 to the edges of the patient contacting portion9348. The patient contacting portion 9348 may lack sufficientextensibility in its width dimension for the non-patient contactingportion 9349 to return, under its bias B, to a flat or flatter shape. Asthe patient contacting portion 9348 holds the non-patient contactingportion 9349 in a deformed configuration against its bias B, after thegas delivery tube 9350 is formed, forces are applied between the patientcontacting portion 9348 and the non-patient contacting portion 9349. Thepatient-contacting portion 9348 may continuously apply forces to thenon-patient contacting portion 9349, against the bias B, preventing thenon-patient contacting portion 9349 from returning to its flat orflatter shape.

Accordingly, the non-patient contacting portion 9349 may apply opposingforces to the patient-contacting portion 9348. The forces applied to thepatient-contacting portion 9348 by the non-patient contacting portion9349, due to the bias B, may result in tension being created in thepatient-contacting portion 9348. This tension is represented by thecharacter T in FIG. 29. The patient contacting portion 9348 may be undertension T across a width of the patient contacting portion 9348, asrepresented in FIG. 29. The non-patient contacting portion 9349 may bepulled by the patient contacting portion 9348 at the edges of thenon-patient contacting portion 9349 (e.g. at the long edges).

As shown in FIG. 29, the non-patient contacting portion 9349 and thepatient-contacting portion 9348 are joined at a pair of seams 9352.

The bias B towards a flatter shape means that when the patientcontacting portion 9348 pulls the edges of the non-patient contactingportion 9349 together, the non-patient contacting portion 9349 may forma rigidised dome-shape rather than collapsing or crinkling. Theresulting headgear tube 9350 may comprise a self-supportingcross-sectional shape. The headgear tube 9350 is able to hold an openshape even in the absence of pressure within the hollow interior of thetube 9350.

There may also be tension in the non-patient contacting portion 9349when joined to the patient contacting portion 9348 due to the bias inthe non-patient contacting portion 9349 back towards a flatter shape.The patient contacting portion 9348 and/or the non-patient contactingportion 9349 may therefore be pretensioned during forming of theheadgear tube 9350.

Accordingly, the tube 9350 is biased towards an open configuration. Thetension in the patient contacting portion 9348 may effectively provideresiliency to the non-patient contacting portion 9349 given it bends thenon-patient contacting portion 9349 into a shape that isself-supporting. The bias B within the non-patient contacting portion9349 and the tension T in the patient contacting portion 9348 may resultin both the patient-contacting portion 9348 and non-patient contactingportion being held taut in cross section, preventing collapse. Theheadgear conduit 9350 also has a pressurised interior in use, which mayalso help maintain patency of the hollow interior.

It will be understood that the bias B and tension T shown in FIG. 29 arerepresentative of the forces acting on and within the headgear tube 9350but that the actual forces may be more complex. For example, in someimplementations the bias B may result from bending of the non-patientcontacting portion 9349 creating both tension and compression within thenon-patient contacting portion 9349. In some implementations, thenon-patient contacting portion 9349 may apply moments to the ends of thepatient contacting portion 9348. In some examples the bias B in thenon-patient contacting portion 9349 may have the effect of impartingcurvature to the patient contacting portion 9348. In some examples, thestiffness and/or resistance to extension in the width dimension of thepatient contacting portion 9348 may be sufficiently high that, under thebias B of the non-patient contacting portion 9349, there issubstantially no or only minimal change in shape of the patientcontacting portion 9348.

The bias in the non-patient contacting portion 9349 of the headgear tube9350 may be provided by elasticity in one or more materials forming thenon-patient contacting portion 9349. A particular stiffness may beimparted to the non-patient contacting portion 9349 and/or patientcontacting portion 9348 by a thermoforming process used to form thenon-patient contacting portion 9349 and/or patient contacting portion9348. Parameters of the thermoforming process (e.g. clamping force,heat, clamping time etc.) may be selected to achieve a predeterminedstiffness of each of the non-patient contacting portion 9349 and thepatient contacting portion 9348.

Alternatively, one or more structural members may be provided to thenon-patient contacting portion 9349 to help the headgear tube 9350maintain an open shape (i.e. a hollow cross-section through which thetherapy flow of gas can pass). In one example, a semi-rigid skeleton isprovided to the non-patient contacting portion 9349. In another example,the non-patient contacting portion 9349 includes an additional layer ofmaterial which is semi-rigid.

While the headgear tubes 9350 may be structured to maintain an openshape in use, they may also be sufficiently flexible to conformcomfortably to the shape of the patient's head. The non-patientcontacting portions 9349, in particular, may be formed from a materialthat is sufficiently stretchable to enable the headgear conduit to bendaround curves of the patient's head. The patient contacting portion 9348may be less stretchable but may lie along a shorter path. That said, thepatient contacting portion 9348 may be sufficiently flexible that it canbend to a lesser radius than the non-patient contacting portion 9349,since the patient contacting portion 9340 lies against the surface ofthe patient's head.

The face contacting portion 9348 may have a higher coefficient offriction with respect to the patient's skin than the non-face contactingportion 9349. The patient-contacting portion 9348 may comprise amedially-facing surface configured to lie against the patient's headhaving a higher coefficient of friction with respect to the patient'sskin than a laterally-facing surface of the non-patient contactingportion 9349. Most or all surfaces of the positioning and stabilisingstructure 9300 may comprise a low friction, soft feel mimicking the feelof bedclothes. However, additional friction may be provided to thepatient contacting side 9348 in order to provide some level of gripwhich may improve stability.

In an alternative example, each headgear tube 9350 may be formed with atextile face contacting portion 9348 and a silicone or TPE non-facecontacting portion 9349. The textile material provided to the facecontacting portion 9348 advantageously may provide a comfortable feel onthe patient's skin, while the silicone material forming the non-facecontacting portion 9349 may provide the advantageous properties ofsilicone, such as flexibility and resiliency and/or the ability tosupport itself in a domed shape to maintain an open hollow interiorthrough which the therapy flow of gas can pass. In one example, theheadgear tubes 9350 may each have a silicone layer in the non-facecontacting portion 9349 and may also have an outermost textile materiallayer to improve the feel of the mask. An advantage of a headgear tube9350 that has a silicone non-face contacting portion 9349, is that theinterior of the tube 9350 is visible through the silicone. The abilityto see the inside of the tube 9350 is advantageous as it may make theconduit easier to clean. In some examples the headgear tubes 9350 may beprovided with windows to enable the patient to view inside the tubes9350, for example during cleaning or for reassurance of the cleanlinessof the hollow interior of each tube 9350. In one example, a headgeartube 9350 comprises an interior transparent layer (e.g. formed fromsilicone or TPE) in at least the non-patient contacting portion 9349covered by an external opaque layer (e.g. formed from a textile and/orfoam layer) and one or more windows formed in the headgear tube 9350 byholes formed in the exterior opaque layer to enable the patient to viewthe hollow interior of the tube 9350 through exposed portions of theinterior transparent layer. In some examples, one or both of the patientcontacting portion 9348 and the non-patient contacting portion 9349 areformed from silicone that is flocked to provide the feel of a textile(e.g. flocked with a textile material or with a material that has thefeel of a textile).

In examples, each headgear tube 9350 may be air impermeable (e.g. it mayhave a laminate or film on the inside), may have textile and/or foamouter layers, may not release an excess of particles into the air flow,and may be comfortable, stable and able to support a seal formingstructure 9100 to maintain an effective seal around the entrance to thepatient's airways. The specific construction of the patient contactingportion 9348 and the non-patient contacting portion 9349 may be asdescribed in other examples disclosed herein. Alternatively, the patientcontacting portion 9348 and/or the non-patient contacting portion 9349may be formed by blow moulding.

In some examples, the headgear tubes 9350 are thermoformed with adistinct face contacting portion 9348 and non-patient contacting portion9349, and each may be formed from a plurality of layers). Alternatively,blow moulding could be used to form the headgear tubes 9350. In someexamples, the headgear tubes 9350 comprise one or more foam or siliconeflocked to produce a textile-like surface.

5.3.3.2.1.9 Layered Construction

In some examples, the patient interface 9000 may comprise gas deliverytubes 9350 (headgear tubes) which each comprise a plurality of layers.Each of the patient contacting portion 9348 and the non-patientcontacting portion 9349 may comprise a plurality of layers. Each layermay provide a different property to the headgear tube 9350. In examples,the layers may provide: air impermeability, particle impermeability,shape forming, bias towards a particularconfiguration/resilience/elasticity, compression resistance,stretchiness and/or a soft textile feel.

FIG. 15 shows a cross section of a headgear tube 9350 according to oneexample. As shown, the tube 9350 is formed by multiple pieces ofmaterial connected together to form an air path. In this example the airpath is suitable for medical use (e.g. it does not release or permitparticles from a material to contaminate the flow of gas). The materialsmay also be connected in a way that does not create bug traps at thejoints (e.g. small spaces/cavities where bacteria can accumulate/grow).

The headgear tube 9350 may comprise a size that varies along the lengthof the tube 9350. In the example shown in FIG. 26, the hollow interiorof the tube 9350 may have a width in a range of 34 mm to 18 mm (e.g., awidth of 24 mm at the superior end of the tube 9350 and a width of 18 mmat the inferior end of the tube). The hollow interior of the tube 9350may have a height within a range of 8 mm to 6 mm (e.g., a height of 8 mmtowards the inferior end of the tube and a height of 6 mm at thesuperior end). The cross-sectional shape of the air path in this examplecomprises a domed shape in which one of the long sides of the crosssection (the non-patient-contacting side 9349 in this example) isoutwardly convex to form a dome-like shape. In other examples of thepresent technology the cross-sectional shape of the air path may be atrapezoidal or rectangular shape.

FIG. 16 shows a schematic view of the cross section of a headgear tube9350 according to one example of the technology. In this example, theheadgear tube 9350 comprises a laminate construction. The headgear tube9350 comprises a patient contacting portion 9348 and a non-patientcontacting portion 9349, each comprising a plurality of layers formingthe conduit. Some layers are layers of material such as plastic film,textile and foam, while other layers are adhesive layers. The outermostlayers are in this example a textile material to provide the appearanceand feel of bedclothes. In other examples the outermost layers maycomprise a foam material.

The innermost layer(s) are formed from an air impermeable material, suchas a thermoplastic film to provide a medically suitable air path. A foamlayer or a spacer fabric layer may also be provided between the textilelayers and the air-impermeable layers on one or both of thepatient-contacting side and non-patient-contacting sides of the airpath, for extra resilience, comfort and/or compression response.

In the example of the present technology shown in FIG. 16, thenon-patient contacting portion 9349 comprises a first outer layer 9371.In this examples the first outer layer 9371 comprises a textilematerial. The textile material may comprise nylon or polyester, asexamples. In other examples the first outer layer 9371 comprises a foammaterial. The non-patient contacting portion 9349 may comprise a firstinner layer 9375 defining a portion of the air path. The first innerlayer 9375 may be air- impermeable. In some examples, the first innerlayer 9375 may comprise thermoplastic material and may be a film. Thefirst inner layer 9375 may comprise a TPU film in some examples. In theFIG. 16 example, between the first outer layer 9371 and the first innerlayer 9375 is an intermediate layer 9373. The intermediate layer 9373comprises a foam material. In other examples the intermediate layer 9373comprises a spacer fabric material. The intermediate layer 9373 mayalternatively comprise a material with a low density similar to or lowerthan the density of foam and spacer fabric materials, such as a meshfabric. Alternatively, in some examples the intermediate layer 9373 maycomprise a material such as silicone, TPE or a gel.

Between an outer layer and an inner layer of the headgear tube 9350, theheadgear tube may comprise at least one adhesive layer. The headgeartube 9350 may comprise a plurality of non-adhesive layers (for examplethe inner layer defining the air path, the intermediate layer and theouter layer) separated by a plurality of adhesive layers. In someexamples, the adhesive layers may comprise film which bonds to thenon-adhesive layers upon heating being applied. In some examples, theadhesive layers comprise a thermoplastic film, such as a TPU film. Wherethe inner layer 9375 is also a film, it may have a higher meltingtemperature than the adhesive layers. In other examples, the adhesivelayers are materials such as films that have adhesive surfaces to adhereto the non-adhesive layers. In further examples, an adhesive substancemay be applied to non-adhesive layers to form an adhesive layer inbetween.

In the example shown in FIG. 16, between the first outer layer 9371 andthe intermediate layer 9373 of the non-patient contacting portion 9349is a first adhesive layer 9372 which bonds these two layers together.Finally, between the first inner layer 9375 and the intermediate layer9373 is a second adhesive layer 9374 configured to bond the first innerlayer 9375 to the intermediate layer 9373.

The patient contacting portion 9348 comprises a second outer layer 9381configured to lie against the patient's head/face in use. In one exampleof the present technology, the second outer layer 9381 comprises atextile material. In other examples the second outer layer 9381comprises a foam material or space fabric. The patient contactingportion 9348, in this example, also comprises a second inner layer 9385defining a portion of the air path. The second inner layer 9385 may beair-impermeable. In some examples the second inner layer 9385 may beformed from a thermoplastic material and may be a film. Between thesecond outer layer 9381 and the second inner layer 9385 the patientcontacting side 9348 comprises an intermediate layer 9383. Theintermediate layer 9383 may comprise a foam material or a spacer fabricmaterial, for example. The intermediate layer 9383 may alternativelycomprise another material with a low density similar to or lower thanthe density of foam and spacer fabric materials. Alternatively, in someexamples the intermediate layer 9383 may comprise a material such assilicone, TPE or a gel.

Between the second outer layer 9381 and the intermediate layer 9383 ofthe patient-contacting side 9348 is a first adhesive layer 9382 whichbonds these two layers together. Finally, between the second inner layer9385 and the intermediate layer 9383 is a second adhesive layer 9384configured to bond the second inner layer 9385 to the intermediate layer9383.

The intermediate layers 9373 and 9383 provide form to the headgear tubes9350. They may provide some rigidity to the overall structure of theheadgear tube 9350 while being comfortable for the patient to lie on.The intermediate layers 9373 and 9383 may enable the headgear tube 9350to have a particular compressive response that is comfortable for thepatient to lie on and have against their head. In some examples, one orboth of the intermediate layers may be omitted. In other examples, oneor both of the outer layers 9371 and 9381 may be omitted. In furtherexamples, there may be multiple intermediate layers formed from foam orspacer fabric materials in either or both of the patient contactingportion 9348 and the non-patient contacting portion 9349.

FIG. 17 shows a cross section of a non-patient contacting portion 9349of a headgear tube 9350 according to another example of the presenttechnology. In this example the non-patient-contacting portion 9349comprises a first inner layer 9375 comprising an air impermeablematerial, a first outer layer 9371 and a first adhesive layer 9372 inbetween. The first outer layer 9371 may comprise a textile material.

Alternatively, the first outer layer 9371 may comprise a foam material.In this example of the present technology, the non-patient-contactingportion 9349 of the conduit does not have an intermediate layer formedfrom foam, spacer fabric or the like. The lack of an intermediate layerin this portion of the headgear tube 9350 may help keep the weight ofthe tube low and facilitate a low-profile headgear conduit.

In some examples, the patient contacting portion 9348 of the headgeartube 9350 comprises a second outer layer 9381, an air impermeable secondinner layer 9385 and an adhesive layer bonding the second outer layer9381 and the second inner layer 9385 together. In such examples theheadgear tube 9350 may not comprise an intermediate layer. The secondouter layer 9381 may comprise a sufficiently thick, stiff and/orresilient material (such as a foam or textile material) to provide forstability, comfort and a suitable compression response.

The intermediate layer of one or both of the non-patient contactingportion 9349 and patient contacting portion 9348, while formed from foamor spacer fabric in the examples above described, may be an alternativecompliant material in other examples of the technology. It could beanother cushion-like material formed from a thick and resilient networkof fibres or could be a gel, silicone or TPE, for example.

In further examples, the tubes 9350 comprise outer layers 9371 and 9381comprising any of a textile, a foam or a spacer fabric material andeither or both of the patient contacting portion 9348 and non-patientcontacting portion 9349 comprises an intermediate layer comprising anyof a textile, a foam or a spacer fabric material.

An appropriate compression response of the headgear tube 9350 isadvantageous for patient comfort. The headgear tubes 9350, comprising acombination of foam and textiles, may comprise a similar compressionresponse to a silicone headgear tube 9350.

In some examples, the intermediate layers 9373 and 9383 of the headgeartube 9350 may be more rigid than exterior layers. The innermost layers(e.g. inner layers 9375 and 9385), which may be formed from a gasimpermeable film, may also increase the overall rigidity of the headgeartube 9350, even if they are not more rigid than other layers.Softness/flexibility in the exterior layers (e.g. outer layers 9371 and9381) is advantageous in providing for a comfortable feel on thepatient's skin, while some rigidity is advantageous in enabling theheadgear tubes 9350 to function as part of a positioning and stabilisingstructure 9300 for the plenum chamber 9200.

In some examples, in the non-patient contacting portion 9349 of theheadgear tube 9350, the intermediate layer 9373 may be thicker than thefirst outer layer 9371. Similarly, in the patient contacting portion9348 of the headgear tube 9350, the intermediate layer 9383 may bethicker than the second outer layer 9381. In one example, theintermediate layers 9373 and 9383 each comprise a foam material (oralternatively a spacer fabric material) and the first outer layer 9371and second outer layer 9381 each comprises a textile material thinnerthan the foam material forming the intermediate layers 9373 and 9383.The intermediate layers 9373 and 9383 may provide stiffness, compressionresistance and resilience to the headgear tube 9350, while the firstouter layer 9371 and second outer layer 9381 may provide the appearanceand feel of bedclothes to the headgear tube 9350.

The innermost layer(s) of the headgear tubes 9350 may comprise asuitable film such as a medical film that is made specifically forthermoforming. In some examples, different films may be used to form theinner layers of each of the patient contacting portion 9348 andnon-patient contacting portion 9349. In one example the film provided tothe non-patient contacting portion 9349 may be suited for thermoformingwith the other layers of the non-patient contacting portion 9349.However, the film provided to the patient contacting portion 9348 may beable to melt to weld the patient contacting portion 9348 to thenon-patient contacting portion 9349.

In some examples, the cross-section of the headgear tube 9350 may not beuniform along the length of the conduit. For example, some layers may bepresent in certain portions of the headgear tube 9350 but not in others.For example, the inferior portion 9363 of the headgear tube 9350 (e.g.the portion that extends from the plenum chamber 9200 to a pointapproximately between the patient's eye and ear) may include an extrarigidising layer to increase rigidity and facilitate efficient transferfor headgear forces to sealing force vectors and/or may include an extratextile sleeve layer configured to further increase the softness of theconduit.

5.3.3.2.2 Headgear Straps

In certain forms of the present technology, the positioning andstabilising structure 9300 comprises at least one headgear strap actingin addition to the tubes 9350 to position and stabilise the seal-formingstructure 9100 in sealing position at the entrance to the patient'sairways. As shown in FIGS. 10 and 11, the patient interfaces 9000 eachcomprise a strap 9310 forming part of the positioning and stabilisingstructure 9300. The strap 9310 may be known as a back strap or a rearheadgear strap, for example. In other examples of the presenttechnology, one or more further straps may be provided. For example, apatient interface 9000 according to an example of the present technologyhaving a full face or oro-nasal cushion module may have a second, lower,strap configured to overlie the back of the patient's neck.

5.3.3.2.2.1 Strap

In the example shown in FIGS. 10 and 11, strap 9310 of the positioningand stabilising structure 9300 is connected between the two tubes 9350positioned on each side of the patient's head and passing around theback of the patient's head, for example overlying or lying inferior tothe occipital bone of the patient's head in use. The strap 9310 connectsto each tube above the patient's ears. In other embodiments, for exampleas part of an oro-nasal patient interface, the positioning andstabilising structure 9300 comprises an upper strap similar to strap9310 and at least one additional lower headgear strap that connectsbetween the tubes and/or cushion module and passes below the patient'sears and around the back of the patient's head. Such a lower headgearstrap may also be connected to an upper strap (e.g. a similar to strap9310).

In certain forms of the technology, the positioning and stabilisingstructure 9300 comprises a mechanism for connecting a headgear strap tothe headgear tubes 9350. The headgear strap may be connected directly orindirectly to the headgear tubes 9350. In the case of the patientinterfaces 9000 shown in FIGS. 10 and 11, for example, a tab 9320configured to connect to strap 9310 projects away from each headgeartube 9350 in a generally posterior direction. The tabs 9320 have holesin them to receive the ends of strap 9310.

In some forms of the present technology, the strap 9310 is adjustable.For example, in the case of the patient interfaces 9000 shown in FIGS.10 and 11, the strap 9310 is, in use, threaded through a hole in theform of a slit 9322 in each tab 9320. The length of the strap 9310between the tabs 9320 may be adjusted by pulling more or less of thestrap 9310 through one or both of the tabs 9320. The strap 9310 may besecured to itself after passing through the slits 9322 in the tabs 9320,for example, with hook-and-loop fastening means. The strap 9310therefore is able to be adjusted to fit around different head sizes. Insome forms of the technology the angle of the strap 9310 relative to theheadgear tubes 9350 or patient's head is able to be adjusted to fitaround the patient's head at different locations. This adjustabilityassists the positioning and stabilising structure 9300 to accommodatedifferent head shapes and sizes.

In some forms of the technology, the strap 9310 exerts a force on theheadgear tubes 9350 to pull them in an at least partially posterior(e.g. rearwards) direction at the locations of the tabs 9320. The strap9310 may also exert a force on the headgear tubes 9350 to pull them inan at least partially inferior (e.g. downwards) direction. The magnitudeof this force may be adjusted by altering the length of the strap 9310between the tabs 9320.

In some forms of the technology, such as the example shown in FIGS. 10and 11, the direction of the force applied to the headgear tubes 9350 bythe strap 9310 may also be altered. This direction may be altered byadjusting the angle of the strap 9310 relative to the headgear tubes9350 or patient's head. In some forms of the technology the location atwhich the strap 9310 exerts a force on the headgear tubes 9350 may bealtered by adjusting the location at which the strap 9310 is secured tothe headgear tubes 9350.

The adjustability of the magnitude and direction of the force applied tothe headgear tubes 9350 by the strap 9310 may advantageously enable thepositioning and stabilising structure 9300 to accommodate a range ofhead sizes and head shapes. The strap 9310 may balance forces in theheadgear tubes 9350 which may assist the headgear to maintain its shapeand an effective seal to the patient's face, while remainingcomfortable.

In some forms of the technology, when worn by a patient, a point on theheadgear tubes 9350 near the tab 9320 will receive a generally upward(e.g. superior) force from the upper portion of the headgear tubes 9350due to tension in the headgear tubes 9350 and, in some examples, due toa biasing mechanism (described in further detail below) acting to keepthe headgear secured to the patient's head.

Additionally, the point on the headgear tubes 9350 near the tab 9320 mayreceive a generally forward (e.g. anterior) and downward (e.g. inferior)reaction force caused by a biasing mechanism acting to urge theseal-forming structure 9100 upwards and into the patient's nose. Thedirections and magnitudes of the forces required for a secure fit andeffective seal may vary between patients based on the position of thepositioning and stabilising structure 9300 on the head, which may varydue to, for example, differences in head shapes and sizes. In some formsof the technology, the adjustability of the rear headgear strap 9310enables the forces to be balanced for a range of head shapes and sizesto hold the positioning and stabilising structure 9300 in a comfortableposition while maintaining an effective seal.

For example, to provide a larger force acting in the posterior (e.g.rearward) direction on the portions of the headgear tubes 9350 proximatethe tabs 9320, the strap 9310 may be adjusted by pulling more of thestrap 9310 through the slits 9322 in the tabs 9320. Doing so will causethe strap 9310 to shorten in length and, especially if the strap 9310 iselastic, to apply a larger force on the headgear tubes 9350 in theposterior (e.g. rearward) direction. Similarly, the angle of the strap9310 may be adjusted as required to balance both the vertical andhorizontal components of the forces acting on the portions of theheadgear tubes 9350 proximate the tabs 9320, across a range of headshapes and sizes.

The strap 9310 may comprise a rectangular cross-section along some orall of its length. Additionally, the strap 9310 may have a profile withone or more rounded edges to provide greater comfort and to reduce therisk of headgear straps marking or irritating the patient. In certainforms of the present technology, a positioning and stabilising structure9300 comprises a strap 9310 that is bendable and e.g. non-rigid. Anadvantage of this aspect is that the strap 9310 is more comfortable fora patient to lie upon while the patient is sleeping.

In certain forms of the present technology, a positioning andstabilising structure 9300 comprises a strap 9310 that comprises two ormore strap bands separated by a split. For example, as shown in FIGS. 10and 11, the strap 9310 comprises a split 9313 configured in use to belocated against the posterior of the patient's head. A split strap 9310may anchor the patient interface 9000 on the patient's head in aparticularly stable fashion in the case of some patient interfacedesigns. The posterior of the patient's head may have complex geometryand the presence of a split 9313 in the strap 9310 may assist the strapto better conform to the back of the patient's head.

5.3.3.2.2.2 Eyelets

As noted above, each of the gas delivery tubes may comprise an eyelet orslit 9322 for connection with a strap. In some examples, the eyelet maybe circular. In other examples, the eyelets may be elongate.Alternatively, the eyelets may have a round side and a straight side.The eyelets may be D-shaped, for example. The eyelets in the exemplarypatient interfaces 9000 shown in FIGS. 10 and 11 are in the form ofslits. In this example, the pair of gas delivery tubes 9350 provide apair of slits 9322 to which a strap 9310 is able to be connected. Thatis, the strap 9310 may connect between the slits 9322. The strap 9310may be constructed and arranged to contact, in use, a region of thepatient's head inferior to or overlaying an occipital bone of thepatient's head. In this example, the eyelets are formed by tabs 9320connected to the tube walls of the tubes 9350.

The tabs 9320 and/or eyelets 9322 may be as described in U.S. PatentApplication No. 62/764,995, the entire contents of each of which areincorporated herein by reference.

5.3.3.2.3 Headgear Architecture

In certain forms, the architecture of the patient interface 9000 is asshown in FIGS. 10 and 11, with a pair of gas delivery tubes 9350 for theleft and right sides of the headgear 9300 engaging at their inferiorends to the cushion module 9150 and at their superior ends to the crownconnector 9360, positioned superior of the patient's head.

In certain other forms, the architecture of the headgear 9300 may be asshown in FIGS. 18 and 19. Instead of separable gas delivery tubes 9350for the left and right sides of the headgear, both sides may be producedtogether as a single thermoformed part. The positioning and stabilisingstructure 9300 in such an example may comprise a left headgear tube 9350(e.g. a left arm or left portion), and a right headgear tube 9350 (e.g.a right arm or right portion). Between the left and right headgear tubes9350 there may be a centre portion or joint that links the left andright headgear tubes 9350. An aperture is provided forming the fluidconnection opening 9390 on the superior portion of the headgear, in thisexample at the joint between the left and right headgear tubes 9350. Theinferior ends of the gas delivery tubes 9350 connect to the cushionmodule 9150 by a removable connection at a cushion module connectionport 9357, for example a snap fit connection. In other examples, theconnection may be permanent, such as by over moulding, welding orgluing. In these forms the inferior ends of the gas delivery tubes 9350are provided with cushion module connection ports 9357 on theirrespective patient contacting sides. In this way, the connection of theheadgear tube 9350 to the cushion module 9150 is hidden or otherwiseobscured from view.

Alternatively, the inferior ends could engage with the cushion moduleusing the snap-fit connections previously described with reference toFIGS. 12A and 12B. This could be either longitudinally from the inferiorends, i.e. the snap-fit connections extend from the ends or,alternatively, the snap-fit connections may be cylindrical in nature andthus could be perpendicular to the inferior ends. This latterarrangement may hide or otherwise obscure the visibility of theconnection between the gas delivery tubes and the cushion module, for amore aesthetically pleasing appearance.

In the example shown in FIG. 18, the headgear tubes 9350 are connectedto an elbow 9610 at a central point along the headgear tubes 9350 atopthe patient's head. The elbow 9610 has only a 45 degree bend, ratherthan a 90 degree bend, and extends in a posterosuperior direction andconnects to a short tube 9616.

The short tube 9616 comprises a connection port 9600 at a distal endthereof. The short tube 9616 decouples the headgear tubes 9350 from thesupply conduit, reducing tube drag.

The tabs 9320 of the positioning and stabilising structure 9300 of FIG.18 are extended in length in comparison to the tabs 9320 of thepositioning and stabilising structure 9300 of FIG. 20. The tabs 9320extend to a point posterior to the patient's ears. Additionally, theslit to which the strap 9310 connects is located at a posterior locationand is angled such the backstrap can connect from an inferior locationwhich may advantageously prevent the strap 9310 from riding up in use.

In certain other forms, the architecture of the headgear 9300 may bereversed such that the left and right headgear tubes 9350 are joined attheir inferior ends and are either permanently connected to a cushionmodule 9150 or are configured to receive the cushion module 9150 (e.g.by a removable connection such as a snap fit). In these forms, thesuperior ends of the gas delivery tubes 9350 may connect to the crownconnector 9360. In some examples, the central portion of the headgeartubes 9350 which connects to the cushion module 9150 is formed to haveshape corresponding to the curvature of the anterior portion of thecushion. That is, the central portion may be preformed. A preformedconnection portion of the headgear tubes 9350 may advantageously enableeasier fitting of the cushion to the headgear tubes 9350 by the user.

In some examples, the headgear tubes 9350 are manipulated into shapewhen fitted to a cushion module 9150.

In some examples in which the headgear tubes 9350 are inseparably joinedat an inferior location (e.g. at the cushion module 9150), the headgeartubes 9350 may comprise a vent 9400 at a central anterior location, suchas on the non-patient-contacting side of the headgear tubes 9350opposite a cushion module 9150 on the patient-contacting side. The vent9400 may be provided by a vent module received in a vent module opening9410 proximate the cushion module 9150, as shown for example in FIGS. 20and 23. The vent 9400 or vent module may be located directly anterior tothe cushion module 9150 to minimise dead space and CO2 build-up in use.

In some examples the vent module may be an overmoulded rigid part withvent holes formed therein. In other examples the vent module may be aremovable rigid part. In further examples the vent module may be adiffuser module configured to provide venting while diffusing the ventflow of gas.

5.3.4 Vent

In one form, the patient interface 3000, 6000, 7000, 8000, 9000, 10000includes at least one vent 3400, 6100, 9400, 9400-1 constructed andarranged to allow for the washout of exhaled gases, e.g. carbon dioxide.

In certain forms the vent is configured to allow a continuous vent flowfrom an interior of the plenum chamber to ambient whilst the pressurewithin the plenum chamber is positive with respect to ambient. The ventis configured such that the vent flow rate has a magnitude sufficient toreduce rebreathing of exhaled CO2 by the patient while maintaining thetherapeutic pressure in the plenum chamber in use. The vent may providea continuous vent flow of gas from the interior of the plenum chamber toambient throughout the patient's respiratory cycle.

One form of vent in accordance with the present technology comprises aplurality of holes, for example, about 20 to about 80 holes, or about 40to about 60 holes, or about 45 to about 55 holes.

The vent 3400, 9400 may be located in the plenum chamber 3200, 9200.Alternatively, the vent 9400-1 is located in a decoupling structure,e.g., a swivel. In another example, the vent 6100 may be located alongthe tube, as shown in the FIG. 4R example. In other forms, the vent maybe located throughout the tube such that a separate vent is not needed.

In the examples shown in FIGS. 10, 11, 20 and 24, the patient interface9000, 10000 may comprise at least one of the vents 9400, 9400-1. In anexample, the patient interface 9000 comprises at least one vent 9400 inthe plenum chamber 9200 and at least one vent 9400-1 in the elbow 9610.In another example, the plenum chamber 9200 comprises two vents 9400.Each vent 9400 on the plenum chamber 9200 comprises an array of holes.The vent 9400-1 on the elbow 9610 also may comprise an array of holes.The vent 9400 of the patient interface 9000 is sized and configured toprovide sufficient gas washout throughout a range of therapeuticpressures.

The patient interface may comprise a diffuser configured to diffuse theflow of air though the vent to reduce vent noise and reduce jetting ofair out of the vent holes. The diffuser may be provided to a cover overthe vent holes. In some examples, the vent may comprise a vent moduleconfigured to be removed from the plenum chamber. The vent module maycomprise a diffuser.

5.3.5 Decoupling Structure(s)

In one form the patient interface 3000, 6000, 7000, 8000, 9000, 10000includes at least one decoupling structure, for example, a swivel or aball and socket. The decoupling structure may be arranged at orproximate the connection port, hub or crown connector to permit theconduit of the air circuit 4170 to move relative to patient interfaceand reduce the risk of destabilising the seal of the seal-formingstructure against the patient's face.

For example, the patient interface 9000, 10000 shown in FIGS. 10 and 11comprises an elbow 9610 configured the swivel with respect to thepositioning and stabilising structure 9300. In this example the elbow9610 is configured to swivel about an axis concentric with a circularopening in the positioning and stabilising structure 9300. In someexamples of the present technology, the elbow 9610 may form part of aball and socket joint to the positioning and stabilising structure 9300.For example, a ring having a partially spherical inner surface may beprovided to the positioning and stabilising structure 9300 and may beconfigured to receive the elbow 9610. The elbow 9610 may have partiallyspherical outer surface complimentary to the partially spherical innersurface of the ring, thereby enabling the elbow 9610 to swivel withrespect to the ring in a plurality of axes.

5.3.6 Connection Port

Connection port 3600, 9600 allows for connection to the air circuit4170. In the forms of the technology shown in FIGS. 4A-4D, for example,the connection port is positioned on top of the patient's head when thepatient interface 3000 is being worn.

In the exemplary patient interface 9000, 10000 shown in FIGS. 10 and 11,the elbow 9610 forms part of the connection port 9600. The elbow 9610,as a decoupling structure, decouples movement of the air circuit 4170from the positioning and stabilising structure 9300 in order to reducetube drag on the positioning and stabilising structure 9300.

In other forms, the connection is configured to be positioned, in use,proximal a top, side, or rear portion of the patient's head. Patientinterfaces in which the connection port is not positioned in front ofthe patient's face may be advantageous as some patient's find a conduitthat connects to a patient interface in front of the face to beunsightly and obtrusive. For example, a conduit connecting to thepatient interface in front of the face may be prone to being tangled upin bedclothes, particularly if the conduit extends downwardly from thepatient interface in use.

5.3.7 Forehead Support

In one form, the patient interface 3000 includes a forehead support3700. In other forms, the patient interface does not include a foreheadsupport. Advantageously, the exemplary patient interface 3000, 6000,7000, 8000, 9000, 10000, shown for example in FIGS. 4A, 4R, 4S, 4X, 10and 11 comprises a positioning and stabilising structure that is able tohold the seal- forming structure in sealing position without connectionto a forehead support or any frame or strap members that lie in front ofthe patient's face at eye level.

5.3.8 Anti-Asphyxia Valve

In one form, the patient interface 3000, 6000, 7000, 8000, 9000, 10000includes an anti-asphyxia valve. In some examples, the patient interfaceincludes a plurality of anti-asphyxia valves. For example, where airflowis provided to a seal-forming structure via two fluid connections, twoanti-asphyxia valves may be provided to the patient interface, one ateach fluid connection to the seal-forming structure.

5.3.9 Ports

In one form of the present technology, a patient interface 3000, 6000,70000, 8000, 9000, 10000 includes one or more ports that allow access tothe volume within the plenum chamber. In one form this allows aclinician to supply supplemental oxygen. In one form, this allows forthe direct measurement of a property of gases within the plenum chamber,such as the pressure.

5.4 RPT Device

An RPT device 4000 in accordance with one aspect of the presenttechnology comprises mechanical, pneumatic, and/or electrical componentsand is configured to execute one or more algorithms 4300, such as any ofthe methods, in whole or in part, described herein. The RPT device 4000may be configured to generate a flow of air for delivery to a patient'sairways, such as to treat one or more of the respiratory conditionsdescribed elsewhere in the present document.

In one form, the RPT device 4000 is constructed and arranged to becapable of delivering a flow of air in a range of −20 L/min to +150L/min while maintaining a positive pressure of at least 6 cmH2O, or atleast 10 cmH2O, or at least 20 cmH2O.

The RPT device may have an external housing 4010, formed in two parts,an upper portion 4012 and a lower portion 4014, as shown in FIG. 31A.Furthermore, the external housing 4010 may include one or more panel(s)4015. The RPT device 4000 comprises a chassis 4016 that supports one ormore internal components of the RPT device 4000. The RPT device 4000 mayinclude a handle 4018.

The pneumatic path of the RPT device 4000 may comprise one or more airpath items, e.g., an inlet air filter 4112, an inlet muffler 4122, apressure generator 4140 capable of supplying air at positive pressure(e.g., a blower 4142), an outlet muffler 4124 and one or moretransducers 4270, such as pressure sensors 4272 and flow rate sensors4274, as shown in FIG. 31B.

One or more of the air path items may be located within a removableunitary structure which will be referred to as a pneumatic block 4020.The pneumatic block 4020 may be located within the external housing4010. In one form a pneumatic block 4020 is supported by, or formed aspart of the chassis 4016.

Referring to FIG. 31C, the RPT device 4000 may have an electrical powersupply 4210, one or more input devices 4220, a central controller 4230,a therapy device controller 4240, a pressure generator 4140, one or moreprotection circuits 4250, memory 4260, transducers 4270, datacommunication interface 4280 and one or more output devices 4290.Electrical components 4200 may be mounted on a single Printed CircuitBoard Assembly (PCBA) 4202. In an alternative form, the RPT device 4000may include more than one PCBA 4202.

5.4.1 RPT Device Mechanical & Pneumatic Components

An RPT device may comprise one or more of the following components in anintegral unit. In an alternative form, one or more of the followingcomponents may be located as respective separate units.

5.4.1.1 Air Filter(s)

An RPT device in accordance with one form of the present technology mayinclude an air filter 4110, or a plurality of air filters 4110.

In one form, an inlet air filter 4112 is located at the beginning of thepneumatic path upstream of a pressure generator 4140.

In one form, an outlet air filter 4114, for example an antibacterialfilter, is located between an outlet of the pneumatic block 4020 and apatient interface 3000.

5.4.1.2 Muffler(s)

An RPT device in accordance with one form of the present technology mayinclude a muffler 4120, or a plurality of mufflers 4120.

In one form of the present technology, an inlet muffler 4122 is locatedin the pneumatic path upstream of a pressure generator 4140.

In one form of the present technology, an outlet muffler 4124 is locatedin the pneumatic path between the pressure generator 4140 and a patientinterface 3000.

5.4.1.3 Pressure Generator

In one form of the present technology, a pressure generator 4140 forproducing a flow, or a supply, of air at positive pressure is acontrollable blower 4142. For example the blower 4142 may include abrushless DC motor 4144 with one or more impellers housed in a blowerhousing, such as in a volute. The blower may be capable of delivering asupply of air, for example at a rate of up to about 120 litres/minute,at a positive pressure in a range from about 4 cmH2O to about 20 cmH2O,or in other forms up to about 30 cmH2O. The blower may be as describedin any one of the following patents or patent applications the contentsof which are incorporated herein by reference in their entirety: U.S.Pat. Nos. 7,866,944; 8,638,014; 8,636,479; and PCT Patent ApplicationPublication No. WO 2013/020167.

The pressure generator 4140 is under the control of the therapy devicecontroller 4240.

In other forms, a pressure generator 4140 may be a piston-driven pump, apressure regulator connected to a high pressure source (e.g. compressedair reservoir), or a bellows.

5.4.1.4 Motor Speed Transducer

In one form of the present technology a motor speed transducer 4276 isused to determine a rotational velocity of the motor 4144 and/or theblower 4142. A motor speed signal from the motor speed transducer 4276may be provided to the therapy device controller 4240. The motor speedtransducer 4276 may, for example, be a speed sensor, such as a Halleffect sensor.

5.4.1.5 Anti-Spill Back Valve

In one form of the present technology, an anti-spill back valve 4160 islocated between the humidifier 5000 and the pneumatic block 4020. Theanti-spill back valve is constructed and arranged to reduce the riskthat water will flow upstream from the humidifier 5000, for example tothe motor 4144.

5.4.1.6 Clock

The RPT device 4000 may include a clock 4232 that is connected to thecentral controller 4230.

5.4.1.7 Data Communication Systems

In one form of the present technology, a data communication interface4280 is provided, and is connected to the central controller 4230. Datacommunication interface 4280 may be connectable to a remote externalcommunication network 4282 and/or a local external communication network4284. The remote external communication network 4282 may be connectableto a remote external device 4286. The local external communicationnetwork 4284 may be connectable to a local external device 4288.

5.4.1.7.1 Display Driver

A display driver 4292 receives as an input the characters, symbols, orimages intended for display on the display 4294, and converts them tocommands that cause the display 4294 to display those characters,symbols, or images.

5.5 Air Circuit

An air circuit 4170 in accordance with an aspect of the presenttechnology is a conduit or a tube constructed and arranged to allow, inuse, a flow of air to travel between two components such as RPT device4000 and the patient interface 3000.

In particular, the air circuit 4170 may be in fluid connection with theoutlet of the pneumatic block 4020 and the patient interface. The aircircuit may be referred to as an air delivery tube. In some cases theremay be separate limbs of the circuit for inhalation and exhalation. Inother cases a single limb is used.

In some forms, the air circuit 4170 may comprise one or more heatingelements configured to heat air in the air circuit, for example tomaintain or raise the temperature of the air. The heating element may bein a form of a heated wire circuit, and may comprise one or moretransducers, such as temperature sensors. In one form, the heated wirecircuit may be helically wound around the axis of the air circuit 4170.The heating element may be in communication with a controller such as acentral controller 4230. One example of an air circuit 4170 comprising aheated wire circuit is described in U.S. Pat. No. 8,733,349, which isincorporated herewithin in its entirety by reference.

5.5.1 Oxygen Delivery

In one form of the present technology, supplemental oxygen 4180 isdelivered to one or more points in the pneumatic path, such as upstreamof the pneumatic block 4020, to the air circuit 4170 and/or to thepatient interface 3000.

5.6 Humidifier 5.6.1 Humidifier Overview

In one form of the present technology there is provided a humidifier5000 (e.g. as shown in FIGS. 32A and 32B) to change the absolutehumidity of air or gas for delivery to a patient relative to ambientair. Typically, the humidifier 5000 is used to increase the absolutehumidity and increase the temperature of the flow of air (relative toambient air) before delivery to the patient's airways.

The humidifier 5000 may comprise a humidifier reservoir 5110, ahumidifier inlet 5002 to receive a flow of air, and a humidifier outlet5004 to deliver a humidified flow of air. In some forms, as shown inFIG. 32A and FIG. 32B, an inlet and an outlet of the humidifierreservoir 5110 may be the humidifier inlet 5002 and the humidifieroutlet 5004 respectively. The humidifier 5000 may further comprise ahumidifier base 5006, which may be adapted to receive the humidifierreservoir 5110 and comprise a heating element 5240.

5.6.2 Humidifier Components 5.6.2.1 Conductive Portion

According to one arrangement, the reservoir 5110 comprises a conductiveportion 5120 configured to allow efficient transfer of heat from theheating element 5240 to the volume of liquid in the reservoir 5110. Inone form, the conductive portion 5120 may be arranged as a plate,although other shapes may also be suitable. All or a part of theconductive portion 5120 may be made of a thermally conductive materialsuch as aluminium (e.g. approximately 2 mm thick, such as 1 mm, 1.5 mm,2.5 mm or 3 mm), another heat conducting metal or some plastics. In somecases, suitable heat conductivity may be achieved with less conductivematerials of suitable geometry.

5.6.2.2 Humidifier Reservoir Dock

In one form, the humidifier 5000 may comprise a humidifier reservoirdock 5130 (as shown in FIG. 32B) configured to receive the humidifierreservoir 5110. In some arrangements, the humidifier reservoir dock 5130may comprise a locking feature such as a locking lever 5135 configuredto retain the reservoir 5110 in the humidifier reservoir dock 5130.

5.6.2.3 Water Level Indicator

The humidifier reservoir 5110 may comprise a water level indicator 5150as shown in FIGS. 32A and 32B. In some forms, the water level indicator5150 may provide one or more indications to a user such as the patient1000 or a care giver regarding a quantity of the volume of water in thehumidifier reservoir 5110. The one or more indications provided by thewater level indicator 5150 may include an indication of a maximum,predetermined volume of water, any portions thereof, such as 25%, 50% or75% or volumes such as 200 ml, 300 ml or 400 ml.

5.7 Glossary

For the purposes of the present technology disclosure, in certain formsof the present technology, one or more of the following definitions mayapply. In other forms of the present technology, alternative definitionsmay apply.

5.7.1 General

Air: In certain forms of the present technology, air may be taken tomean atmospheric air, and in other forms of the present technology airmay be taken to mean some other combination of breathable gases, e.g.atmospheric air enriched with oxygen.

Ambient: In certain forms of the present technology, the term ambientwill be taken to mean (i) external of the treatment system or patient,and (ii) immediately surrounding the treatment system or patient.

For example, ambient humidity with respect to a humidifier may be thehumidity of air immediately surrounding the humidifier, e.g. thehumidity in the room where a patient is sleeping. Such ambient humiditymay be different to the humidity outside the room where a patient issleeping.

In another example, ambient pressure may be the pressure immediatelysurrounding or external to the body.

In certain forms, ambient (e.g., acoustic) noise may be considered to bethe background noise level in the room where a patient is located, otherthan for example, noise generated by an RPT device or emanating from amask or patient interface. Ambient noise may be generated by sourcesoutside the room.

Automatic Positive Airway Pressure (APAP) therapy: CPAP therapy in whichthe treatment pressure is automatically adjustable, e.g. from breath tobreath, between minimum and maximum limits, depending on the presence orabsence of indications of SDB events.

Continuous Positive Airway Pressure (CPAP) therapy: Respiratory pressuretherapy in which the treatment pressure is approximately constantthrough a respiratory cycle of a patient. In some forms, the pressure atthe entrance to the airways will be slightly higher during exhalation,and slightly lower during inhalation. In some forms, the pressure willvary between different respiratory cycles of the patient, for example,being increased in response to detection of indications of partial upperairway obstruction, and decreased in the absence of indications ofpartial upper airway obstruction.

Flow rate: The volume (or mass) of air delivered per unit time. Flowrate may refer to an instantaneous quantity. In some cases, a referenceto flow rate will be a reference to a scalar quantity, namely a quantityhaving magnitude only. In other cases, a reference to flow rate will bea reference to a vector quantity, namely a quantity having bothmagnitude and direction. Flow rate may be given the symbol Q. ‘Flowrate’ is sometimes shortened to simply ‘flow’ or ‘airflow’.

In the example of patient respiration, a flow rate may be nominallypositive for the inspiratory portion of a breathing cycle of a patient,and hence negative for the expiratory portion of the breathing cycle ofa patient. Total flow rate, Qt, is the flow rate of air leaving the RPTdevice. Vent flow rate, Qv, is the flow rate of air leaving a vent toallow washout of exhaled gases. Leak flow rate, Ql, is the flow rate ofleak from a patient interface system or elsewhere. Respiratory flowrate, Qr, is the flow rate of air that is received into the patient'srespiratory system.

Humidifier: The word humidifier will be taken to mean a humidifyingapparatus constructed and arranged, or configured with a physicalstructure to be capable of providing a therapeutically beneficial amountof water (H₂O) vapour to a flow of air to ameliorate a medicalrespiratory condition of a patient.

Leak: The word leak will be taken to be an unintended flow of air. Inone example, leak may occur as the result of an incomplete seal betweena mask and a patient's face. In another example leak may occur in aswivel elbow to the ambient.

Noise, conducted (acoustic): Conducted noise in the present documentrefers to noise which is carried to the patient by the pneumatic path,such as the air circuit and the patient interface as well as the airtherein. In one form, conducted noise may be quantified by measuringsound pressure levels at the end of an air circuit.

Noise, radiated (acoustic): Radiated noise in the present documentrefers to noise which is carried to the patient by the ambient air. Inone form, radiated noise may be quantified by measuring soundpower/pressure levels of the object in question according to ISO 3744.

Noise, vent (acoustic): Vent noise in the present document refers tonoise which is generated by the flow of air through any vents such asvent holes of the patient interface.

Patient: A person, whether or not they are suffering from a respiratorycondition.

Pressure: Force per unit area. Pressure may be expressed in a range ofunits, including cmH2O, g-f/cm² and hectopascal. 1 cmH2O is equal to 1g-f/cm² and is approximately 0.98 hectopascal. In this specification,unless otherwise stated, pressure is given in units of cmH2O.

The pressure in the patient interface is given the symbol Pm, while thetreatment pressure, which represents a target value to be achieved bythe mask pressure Pm at the current instant of time, is given the symbolPt.

Respiratory Pressure Therapy (RPT): The application of a supply of airto an entrance to the airways at a treatment pressure that is typicallypositive with respect to atmosphere.

Ventilator: A mechanical device that provides pressure support to apatient to perform some or all of the work of breathing.

5.7.1.1 Materials

Silicone or Silicone Elastomer: A synthetic rubber. In thisspecification, a reference to silicone is a reference to liquid siliconerubber (LSR) or a compression moulded silicone rubber (CMSR). One formof commercially available LSR is SILASTIC (included in the range ofproducts sold under this trademark), manufactured by Dow Corning.Another manufacturer of LSR is Wacker. Unless otherwise specified to thecontrary, an exemplary form of LSR has a Shore A (or Type A) indentationhardness in the range of about 35 to about 45 as measured using ASTMD2240.

Polycarbonate: a thermoplastic polymer of Bisphenol-A Carbonate.

5.7.1.2 Mechanical Properties

Resilience: Ability of a material to absorb energy when deformedelastically and to release the energy upon unloading.

Resilient: Will release substantially all of the energy when unloaded.Includes e.g. certain silicones, and thermoplastic elastomers.

Hardness: The ability of a material per se to resist deformation (e.g.described by a Young's Modulus, or an indentation hardness scalemeasured on a standardised sample size).

-   -   ‘Soft’ materials may include silicone or thermo-plastic        elastomer (TPE), and may, e.g. readily deform under finger        pressure.    -   ‘Hard’ materials may include polycarbonate, polypropylene, steel        or aluminium, and may not e.g. readily deform under finger        pressure.

Stiffness (or rigidity) of a structure or component: The ability of thestructure or component to resist deformation in response to an appliedload. The load may be a force or a moment, e.g. compression, tension,bending or torsion. The structure or component may offer differentresistances in different directions.

Floppy structure or component: A structure or component that will changeshape, e.g. bend, when caused to support its own weight, within arelatively short period of time such as 1 second.

Rigid structure or component: A structure or component that will notsubstantially change shape when subject to the loads typicallyencountered in use. An example of such a use may be setting up andmaintaining a patient interface in sealing relationship with an entranceto a patient's airways, e.g. at a load of approximately 20 to 30 cmH2Opressure.

As an example, an I-beam may comprise a different bending stiffness(resistance to a bending load) in a first direction in comparison to asecond, orthogonal direction. In another example, a structure orcomponent may be floppy in a first direction and rigid in a seconddirection.

5.7.2 Respiratory Cycle

Apnea: According to some definitions, an apnea is said to have occurredwhen flow falls below a predetermined threshold for a duration, e.g. 10seconds. An obstructive apnea will be said to have occurred when,despite patient effort, some obstruction of the airway does not allowair to flow. A central apnea will be said to have occurred when an apneais detected that is due to a reduction in breathing effort, or theabsence of breathing effort, despite the airway being patent. A mixedapnea occurs when a reduction or absence of breathing effort coincideswith an obstructed airway.

Breathing rate: The rate of spontaneous respiration of a patient,usually measured in breaths per minute.

Duty cycle: The ratio of inhalation time, Ti to total breath time, Ttot.

Effort (breathing): The work done by a spontaneously breathing personattempting to breathe.

Expiratory portion of a breathing cycle: The period from the start ofexpiratory flow to the start of inspiratory flow.

Flow limitation: Flow limitation will be taken to be the state ofaffairs in a patient's respiration where an increase in effort by thepatient does not give rise to a corresponding increase in flow. Whereflow limitation occurs during an inspiratory portion of the breathingcycle it may be described as inspiratory flow limitation. Where flowlimitation occurs during an expiratory portion of the breathing cycle itmay be described as expiratory flow limitation.

Types of flow limited inspiratory waveforms:

-   -   (ii) Flattened: Having a rise followed by a relatively flat        portion, followed by a fall.    -   (ii) M-shaped: Having two local peaks, one at the leading edge,        and one at the trailing edge, and a relatively flat portion        between the two peaks.    -   (iii) Chair-shaped: Having a single local peak, the peak being        at the leading edge, followed by a relatively flat portion.    -   (iv) Reverse-chair shaped: Having a relatively flat portion        followed by single local peak, the peak being at the trailing        edge.

Hypopnea: According to some definitions, a hypopnea is taken to be areduction in flow, but not a cessation of flow. In one form, a hypopneamay be said to have occurred when there is a reduction in flow below athreshold rate for a duration. A central hypopnea will be said to haveoccurred when a hypopnea is detected that is due to a reduction inbreathing effort. In one form in adults, either of the following may beregarded as being hypopneas:

-   -   (ii) a 30% reduction in patient breathing for at least 10        seconds plus an associated 4% desaturation; or    -   (ii) a reduction in patient breathing (but less than 50%) for at        least 10 seconds, with an associated desaturation of at least 3%        or an arousal.

Hyperpnea: An increase in flow to a level higher than normal.

Inspiratory portion of a breathing cycle: The period from the start ofinspiratory flow to the start of expiratory flow will be taken to be theinspiratory portion of a breathing cycle.

Patency (airway): The degree of the airway being open, or the extent towhich the airway is open. A patent airway is open. Airway patency may bequantified, for example with a value of one (1) being patent, and avalue of zero (0), being closed (obstructed).

Positive End-Expiratory Pressure (PEEP): The pressure above atmospherein the lungs that exists at the end of expiration.

Peak flow rate (Qpeak): The maximum value of flow rate during theinspiratory portion of the respiratory flow waveform.

Respiratory flow rate, patient airflow rate, respiratory airflow rate(Qr): These terms may be understood to refer to the RPT device'sestimate of respiratory flow rate, as opposed to “true respiratory flowrate” or “true respiratory flow rate”, which is the actual respiratoryflow rate experienced by the patient, usually expressed in litres perminute.

Tidal volume (Vt): The volume of air inhaled or exhaled during normalbreathing, when extra effort is not applied. In principle theinspiratory volume Vi (the volume of air inhaled) is equal to theexpiratory volume Ve (the volume of air exhaled), and therefore a singletidal volume Vt may be defined as equal to either quantity. In practicethe tidal volume Vt is estimated as some combination, e.g. the mean, ofthe inspiratory volume Vi and the expiratory volume Ve.

(inhalation) Time (Ti): The duration of the inspiratory portion of therespiratory flow rate waveform.

(exhalation) Time (Te): The duration of the expiratory portion of therespiratory flow rate waveform.

(total) Time (Ttot): The total duration between the start of oneinspiratory portion of a respiratory flow rate waveform and the start ofthe following inspiratory portion of the respiratory flow rate waveform.

Upper airway obstruction (UAO): includes both partial and total upperairway obstruction. This may be associated with a state of flowlimitation, in which the flow rate increases only slightly or may evendecrease as the pressure difference across the upper airway increases(Starling resistor behaviour).

Ventilation (Vent): A measure of a rate of gas being exchanged by thepatient's respiratory system. Measures of ventilation may include one orboth of inspiratory and expiratory flow, per unit time. When expressedas a volume per minute, this quantity is often referred to as “minuteventilation”. Minute ventilation is sometimes given simply as a volume,understood to be the volume per minute.

5.7.3 Ventilation

Adaptive Servo-Ventilator (ASV): A servo-ventilator that has achangeable, rather than fixed target ventilation. The changeable targetventilation may be learned from some characteristic of the patient, forexample, a respiratory characteristic of the patient.

Backup rate: A parameter of a ventilator that establishes the minimumbreathing rate (typically in number of breaths per minute) that theventilator will deliver to the patient, if not triggered by spontaneousrespiratory effort.

Cycled: The termination of a ventilator's inspiratory phase. When aventilator delivers a breath to a spontaneously breathing patient, atthe end of the inspiratory portion of the breathing cycle, theventilator is said to be cycled to stop delivering the breath.

Expiratory positive airway pressure (EPAP): a base pressure, to which apressure varying within the breath is added to produce the desired maskpressure which the ventilator will attempt to achieve at a given time.

End expiratory pressure (EEP): Desired mask pressure which theventilator will attempt to achieve at the end of the expiratory portionof the breath. If the pressure waveform template □(□) is zero-valued atthe end of expiration, i.e. □(□)=0 when □=1, the EEP is equal to theEPAP.

Inspiratory positive airway pressure (IPAP): Maximum desired maskpressure which the ventilator will attempt to achieve during theinspiratory portion of the breath.

Pressure support: A number that is indicative of the increase inpressure during ventilator inspiration over that during ventilatorexpiration, and generally means the difference in pressure between themaximum value during inspiration and the base pressure (e.g.,PS=IPAP−EPAP). In some contexts pressure support means the differencewhich the ventilator aims to achieve, rather than what it actuallyachieves.

Servo-ventilator: A ventilator that measures patient ventilation, has atarget ventilation, and which adjusts the level of pressure support tobring the patient ventilation towards the target ventilation.

Spontaneous/Timed (S/T): A mode of a ventilator or other device thatattempts to detect the initiation of a breath of a spontaneouslybreathing patient. If however, the device is unable to detect a breathwithin a predetermined period of time, the device will automaticallyinitiate delivery of the breath.

Swing: Equivalent term to pressure support.

Triggered: When a ventilator delivers a breath of air to a spontaneouslybreathing patient, it is said to be triggered to do so at the initiationof the respiratory portion of the breathing cycle by the patient'sefforts.

Typical recent ventilation: The typical recent ventilation Vtyp is thevalue around which recent measures of ventilation over somepredetermined timescale tend to cluster. For example, a measure of thecentral tendency of the measures of ventilation over recent history maybe a suitable value of a typical recent ventilation.

5.7.4 Anatomy 5.7.4.1 Anatomy of the Face

Ala: the external outer wall or “wing” of each nostril (plural: alar)

Alar angle:

Alare: The most lateral point on the nasal ala.

Alar curvature (or alar crest) point: The most posterior point in thecurved base line of each ala, found in the crease formed by the union ofthe ala with the cheek.

Auricle: The whole external visible part of the ear.

(nose) Bony framework: The bony framework of the nose comprises thenasal bones, the frontal process of the maxillae and the nasal part ofthe frontal bone.

(nose) Cartilaginous framework: The cartilaginous framework of the nosecomprises the septal, lateral, major and minor cartilages.

Columella: the strip of skin that separates the nares and which runsfrom the pronasale to the upper lip.

Columella angle: The angle between the line drawn through the midpointof the nostril aperture and a line drawn perpendicular to the Frankforthorizontal while intersecting subnasale.

Frankfort horizontal plane: A line extending from the most inferiorpoint of the orbital margin to the left tragion. The tragion is thedeepest point in the notch superior to the tragus of the auricle.

Glabella: Located on the soft tissue, the most prominent point in themidsagittal plane of the forehead.

Lateral nasal cartilage: A generally triangular plate of cartilage. Itssuperior margin is attached to the nasal bone and frontal process of themaxilla, and its inferior margin is connected to the greater alarcartilage.

Lip, lower (labrale inferius):

Lip, upper (labrale superius):

Greater alar cartilage: A plate of cartilage lying below the lateralnasal cartilage. It is curved around the anterior part of the naris. Itsposterior end is connected to the frontal process of the maxilla by atough fibrous membrane containing three or four minor cartilages of theala.

Nares (Nostrils): Approximately ellipsoidal apertures forming theentrance to the nasal cavity. The singular form of nares is naris(nostril). The nares are separated by the nasal septum.

Naso-labial sulcus or Naso-labial fold: The skin fold or groove thatruns from each side of the nose to the corners of the mouth, separatingthe cheeks from the upper lip.

Naso-labial angle: The angle between the columella and the upper lip,while intersecting subnasale.

Otobasion inferior: The lowest point of attachment of the auricle to theskin of the face.

Otobasion superior: The highest point of attachment of the auricle tothe skin of the face.

Pronasale: the most protruded point or tip of the nose, which can beidentified in lateral view of the rest of the portion of the head.

Philtrum: the midline groove that runs from lower border of the nasalseptum to the top of the lip in the upper lip region.

Pogonion: Located on the soft tissue, the most anterior midpoint of thechin.

Ridge (nasal): The nasal ridge is the midline prominence of the nose,extending from the Sellion to the Pronasale.

Sagittal plane: A vertical plane that passes from anterior (front) toposterior (rear). The midsagittal plane is a sagittal plane that dividesthe body into right and left halves.

Sellion: Located on the soft tissue, the most concave point overlyingthe area of the frontonasal suture.

Septal cartilage (nasal): The nasal septal cartilage forms part of theseptum and divides the front part of the nasal cavity.

Subalare: The point at the lower margin of the alar base, where the alarbase joins with the skin of the superior (upper) lip.

Subnasal point: Located on the soft tissue, the point at which thecolumella merges with the upper lip in the midsagittal plane.

Supramenton: The point of greatest concavity in the midline of the lowerlip between labrale inferius and soft tissue pogonion

5.7.4.2 Anatomy of the Skull

Frontal bone: The frontal bone includes a large vertical portion, thesquama frontalis, corresponding to the region known as the forehead.

Mandible: The mandible forms the lower jaw. The mental protuberance isthe bony protuberance of the jaw that forms the chin.

Maxilla: The maxilla forms the upper jaw and is located above themandible and below the orbits. The frontal process of the maxillaprojects upwards by the side of the nose, and forms part of its lateralboundary.

Nasal bones: The nasal bones are two small oblong bones, varying in sizeand form in different individuals; they are placed side by side at themiddle and upper part of the face, and form, by their junction, the“bridge” of the nose.

Nasion: The intersection of the frontal bone and the two nasal bones, adepressed area directly between the eyes and superior to the bridge ofthe nose.

Occipital bone: The occipital bone is situated at the back and lowerpart of the cranium. It includes an oval aperture, the foramen magnum,through which the cranial cavity communicates with the vertebral canal.The curved plate behind the foramen magnum is the squama occipitalis.

Orbit: The bony cavity in the skull to contain the eyeball.

Parietal bones: The parietal bones are the bones that, when joinedtogether, form the roof and sides of the cranium.

Temporal bones: The temporal bones are situated on the bases and sidesof the skull, and support that part of the face known as the temple.

Zygomatic bones: The face includes two zygomatic bones, located in theupper and lateral parts of the face and forming the prominence of thecheek.

5.7.4.3 Anatomy of the Respiratory System

Diaphragm: A sheet of muscle that extends across the bottom of the ribcage. The diaphragm separates the thoracic cavity, containing the heart,lungs and ribs, from the abdominal cavity. As the diaphragm contractsthe volume of the thoracic cavity increases and air is drawn into thelungs.

Larynx: The larynx, or voice box houses the vocal folds and connects theinferior part of the pharynx (hypopharynx) with the trachea.

Lungs: The organs of respiration in humans. The conducting zone of thelungs contains the trachea, the bronchi, the bronchioles, and theterminal bronchioles. The respiratory zone contains the respiratorybronchioles, the alveolar ducts, and the alveoli.

Nasal cavity: The nasal cavity (or nasal fossa) is a large air filledspace above and behind the nose in the middle of the face. The nasalcavity is divided in two by a vertical fin called the nasal septum. Onthe sides of the nasal cavity are three horizontal outgrowths callednasal conchae (singular “concha”) or turbinates. To the front of thenasal cavity is the nose, while the back blends, via the choanae, intothe nasopharynx.

Pharynx: The part of the throat situated immediately inferior to (below)the nasal cavity, and superior to the oesophagus and larynx. The pharynxis conventionally divided into three sections: the nasopharynx(epipharynx) (the nasal part of the pharynx), the oropharynx(mesopharynx) (the oral part of the pharynx), and the laryngopharynx(hypopharynx).

5.7.5 Patient Interface

Anti-asphyxia valve (AAV): The component or sub-assembly of a masksystem that, by opening to atmosphere in a failsafe manner, reduces therisk of excessive CO₂ rebreathing by a patient.

Elbow: An elbow is an example of a structure that directs an axis offlow of air travelling therethrough to change direction through anangle. In one form, the angle may be approximately 90 degrees. Inanother form, the angle may be more, or less than 90 degrees. The elbowmay have an approximately circular cross-section. In another form theelbow may have an oval or a rectangular cross-section. In certain formsan elbow may be rotatable with respect to a mating component, e.g. about360 degrees. In certain forms an elbow may be removable from a matingcomponent, e.g. via a snap connection. In certain forms, an elbow may beassembled to a mating component via a one-time snap during manufacture,but not removable by a patient.

Frame: Frame will be taken to mean a mask structure that bears the loadof tension between two or more points of connection with a headgear. Amask frame may be a non-airtight load bearing structure in the mask.However, some forms of mask frame may also be air-tight.

Headgear: Headgear will be taken to mean a form of positioning andstabilizing structure designed for use on a head. For example theheadgear may comprise a collection of one or more struts, ties andstiffeners configured to locate and retain a patient interface inposition on a patient's face for delivery of respiratory therapy. Someties are formed of a soft, flexible, elastic material such as alaminated composite of foam and fabric.

Membrane: Membrane will be taken to mean a typically thin element thathas, preferably, substantially no resistance to bending, but hasresistance to being stretched.

Plenum chamber: a mask plenum chamber will be taken to mean a portion ofa patient interface having walls at least partially enclosing a volumeof space, the volume having air therein pressurised above atmosphericpressure in use. A shell may form part of the walls of a mask plenumchamber.

Seal: May be a noun form (“a seal”) which refers to a structure, or averb form (“to seal”) which refers to the effect. Two elements may beconstructed and/or arranged to ‘seal’ or to effect ‘sealing’therebetween without requiring a separate ‘seal’ element per se.

Shell: A shell will be taken to mean a curved, relatively thin structurehaving bending, tensile and compressive stiffness. For example, a curvedstructural wall of a mask may be a shell. In some forms, a shell may befaceted. In some forms a shell may be airtight. In some forms a shellmay not be airtight.

Stiffener: A stiffener will be taken to mean a structural componentdesigned to increase the bending resistance of another component in atleast one direction.

Strut: A strut will be taken to be a structural component designed toincrease the compression resistance of another component in at least onedirection.

Swivel (noun): A subassembly of components configured to rotate about acommon axis, preferably independently, preferably under low torque. Inone form, the swivel may be constructed to rotate through an angle of atleast 360 degrees. In another form, the swivel may be constructed torotate through an angle less than 360 degrees. When used in the contextof an air delivery conduit, the sub-assembly of components preferablycomprises a matched pair of cylindrical conduits. There may be little orno leak flow of air from the swivel in use.

Tie (noun): A structure designed to resist tension.

Vent: (noun): A structure that allows a flow of air from an interior ofthe mask, or conduit, to ambient air for clinically effective washout ofexhaled gases. For example, a clinically effective washout may involve aflow rate of about 10 litres per minute to about 100 litres per minute,depending on the mask design and treatment pressure.

5.7.6 Shape of Structures

Products in accordance with the present technology may comprise one ormore three-dimensional mechanical structures, for example a mask cushionor an impeller. The three-dimensional structures may be bounded bytwo-dimensional surfaces. These surfaces may be distinguished using alabel to describe an associated surface orientation, location, function,or some other characteristic. For example a structure may comprise oneor more of an anterior surface, a posterior surface, an interior surfaceand an exterior surface. In another example, a seal-forming structuremay comprise a face-contacting (e.g. outer) surface, and a separatenon-face-contacting (e.g. underside or inner) surface. In anotherexample, a structure may comprise a first surface and a second surface.

To facilitate describing the shape of the three-dimensional structuresand the surfaces, we first consider a cross-section through a surface ofthe structure at a point, p. See FIG. 3B to FIG. 3F, which illustrateexamples of cross-sections at point p on a surface, and the resultingplane curves. FIGS. 3B to 3F also illustrate an outward normal vector atp. The outward normal vector at p points away from the surface. In someexamples we describe the surface from the point of view of an imaginarysmall person standing upright on the surface.

5.7.6.1 Curvature in One Dimension

The curvature of a plane curve at p may be described as having a sign(e.g. positive, negative) and a magnitude (e.g. 1/radius of a circlethat just touches the curve at p).

Positive curvature: If the curve at p turns towards the outward normal,the curvature at that point will be taken to be positive (if theimaginary small person leaves the point p they must walk uphill). SeeFIG. 3B (relatively large positive curvature compared to FIG. 3C) andFIG. 3C (relatively small positive curvature compared to FIG. 3B). Suchcurves are often referred to as concave.

Zero curvature: If the curve at p is a straight line, the curvature willbe taken to be zero (if the imaginary small person leaves the point p,they can walk on a level, neither up nor down). See FIG. 3D.

Negative curvature: If the curve at p turns away from the outwardnormal, the curvature in that direction at that point will be taken tobe negative (if the imaginary small person leaves the point p they mustwalk downhill). See FIG. 3E (relatively small negative curvaturecompared to FIG. 3F) and FIG. 3F (relatively large negative curvaturecompared to FIG. 3E). Such curves are often referred to as convex.

5.7.6.2 Curvature of Two Dimensional Surfaces

A description of the shape at a given point on a two-dimensional surfacein accordance with the present technology may include multiple normalcross-sections. The multiple cross-sections may cut the surface in aplane that includes the outward normal (a “normal plane”), and eachcross-section may be taken in a different direction. Each cross-sectionresults in a plane curve with a corresponding curvature. The differentcurvatures at that point may have the same sign, or a different sign.Each of the curvatures at that point has a magnitude, e.g. relativelysmall. The plane curves in FIGS. 3B to 3F could be examples of suchmultiple cross-sections at a particular point.

Principal curvatures and directions: The directions of the normal planeswhere the curvature of the curve takes its maximum and minimum valuesare called the principal directions. In the examples of FIG. 3B to FIG.3F, the maximum curvature occurs in FIG. 3B, and the minimum occurs inFIG. 3F, hence FIG. 3B and FIG. 3F are cross sections in the principaldirections. The principal curvatures at p are the curvatures in theprincipal directions.

Region of a surface: A connected set of points on a surface. The set ofpoints in a region may have similar characteristics, e.g. curvatures orsigns.

Saddle region: A region where at each point, the principal curvatureshave opposite signs, that is, one is positive, and the other is negative(depending on the direction to which the imaginary person turns, theymay walk uphill or downhill).

Dome region: A region where at each point the principal curvatures havethe same sign, e.g. both positive (a “concave dome”) or both negative (a“convex dome”).

Cylindrical region: A region where one principal curvature is zero (or,for example, zero within manufacturing tolerances) and the otherprincipal curvature is non-zero.

Planar region: A region of a surface where both of the principalcurvatures are zero (or, for example, zero within manufacturingtolerances).

Edge of a surface: A boundary or limit of a surface or region.

Path: In certain forms of the present technology, ‘path’ will be takento mean a path in the mathematical—topological sense, e.g. a continuousspace curve from f(0) to f(1) on a surface. In certain forms of thepresent technology, a ‘path’ may be described as a route or course,including e.g. a set of points on a surface. (The path for the imaginaryperson is where they walk on the surface, and is analogous to a gardenpath).

Path length: In certain forms of the present technology, ‘path length’will be taken to mean the distance along the surface fromf(0) to f(1),that is, the distance along the path on the surface. There may be morethan one path between two points on a surface and such paths may havedifferent path lengths. (The path length for the imaginary person wouldbe the distance they have to walk on the surface along the path).

Straight-line distance: The straight-line distance is the distancebetween two points on a surface, but without regard to the surface. Onplanar regions, there would be a path on the surface having the samepath length as the straight-line distance between two points on thesurface. On non-planar surfaces, there may be no paths having the samepath length as the straight-line distance between two points. (For theimaginary person, the straight-line distance would correspond to thedistance ‘as the crow flies’.)

5.7.6.3 Space Curves

Space curves: Unlike a plane curve, a space curve does not necessarilylie in any particular plane. A space curve may be closed, that is,having no endpoints. A space curve may be considered to be aone-dimensional piece of three-dimensional space. An imaginary personwalking on a strand of the DNA helix walks along a space curve. Atypical human left ear comprises a helix, which is a left-hand helix,see FIG. 3Q. A typical human right ear comprises a helix, which is aright-hand helix, see FIG. 3R. FIG. 3S shows a right-hand helix. Theedge of a structure, e.g. the edge of a membrane or impeller, may followa space curve. In general, a space curve may be described by a curvatureand a torsion at each point on the space curve. Torsion is a measure ofhow the curve turns out of a plane. Torsion has a sign and a magnitude.The torsion at a point on a space curve may be characterised withreference to the tangent, normal and binormal vectors at that point.

Tangent unit vector (or unit tangent vector): For each point on a curve,a vector at the point specifies a direction from that point, as well asa magnitude. A tangent unit vector is a unit vector pointing in the samedirection as the curve at that point. If an imaginary person were flyingalong the curve and fell off her vehicle at a particular point, thedirection of the tangent vector is the direction she would betravelling.

Unit normal vector: As the imaginary person moves along the curve, thistangent vector itself changes. The unit vector pointing in the samedirection that the tangent vector is changing is called the unitprincipal normal vector. It is perpendicular to the tangent vector.

Binormal unit vector: The binormal unit vector is perpendicular to boththe tangent vector and the principal normal vector. Its direction may bedetermined by a right-hand rule (see e.g. FIG. 3P), or alternatively bya left-hand rule (FIG. 3O).

Osculating plane: The plane containing the unit tangent vector and theunit principal normal vector. See FIGS. 3O and 3P.

Torsion of a space curve: The torsion at a point of a space curve is themagnitude of the rate of change of the binormal unit vector at thatpoint. It measures how much the curve deviates from the osculatingplane. A space curve which lies in a plane has zero torsion. A spacecurve which deviates a relatively small amount from the osculating planewill have a relatively small magnitude of torsion (e.g. a gently slopinghelical path). A space curve which deviates a relatively large amountfrom the osculating plane will have a relatively large magnitude oftorsion (e.g. a steeply sloping helical path). With reference to FIG.3S, since T2>T1, the magnitude of the torsion near the top coils of thehelix of FIG. 3S is greater than the magnitude of the torsion of thebottom coils of the helix of FIG. 3S

With reference to the right-hand rule of FIG. 3P, a space curve turningtowards the direction of the right-hand binormal may be considered ashaving a right-hand positive torsion (e.g. a right-hand helix as shownin FIG. 3S). A space curve turning away from the direction of theright-hand binormal may be considered as having a right-hand negativetorsion (e.g. a left-hand helix).

Equivalently, and with reference to a left-hand rule (see FIG. 3O), aspace curve turning towards the direction of the left-hand binormal maybe considered as having a left-hand positive torsion (e.g. a left-handhelix). Hence left-hand positive is equivalent to right-hand negative.See FIG. 3T.

5.7.6.4 Holes

A surface may have a one-dimensional hole, e.g. a hole bounded by aplane curve or by a space curve. Thin structures (e.g. a membrane) witha hole, may be described as having a one-dimensional hole. See forexample the one dimensional hole in the surface of structure shown inFIG. 3I, bounded by a plane curve.

A structure may have a two-dimensional hole, e.g. a hole bounded by asurface. For example, an inflatable tyre has a two dimensional holebounded by the interior surface of the tyre. In another example, abladder with a cavity for air or gel could have a two-dimensional hole.See for example the cushion of FIG. 3L and the example cross-sectionstherethrough in FIG. 3M and FIG. 3N, with the interior surface boundinga two dimensional hole indicated. In a yet another example, a conduitmay comprise a one-dimension hole (e.g. at its entrance or at its exit),and a two-dimension hole bounded by the inside surface of the conduit.See also the two dimensional hole through the structure shown in FIG.3K, bounded by a surface as shown.

5.8 Other Remarks

Unless the context clearly dictates otherwise and where a range ofvalues is provided, it is understood that each intervening value, to thetenth of the unit of the lower limit, between the upper and lower limitof that range, and any other stated or intervening value in that statedrange is encompassed within the technology. The upper and lower limitsof these intervening ranges, which may be independently included in theintervening ranges, are also encompassed within the technology, subjectto any specifically excluded limit in the stated range. Where the statedrange includes one or both of the limits, ranges excluding either orboth of those included limits are also included in the technology.

Furthermore, where a value or values are stated herein as beingimplemented as part of the technology, it is understood that such valuesmay be approximated, unless otherwise stated, and such values may beutilized to any suitable significant digit to the extent that apractical technical implementation may permit or require it.

Unless defined otherwise, all technical and scientific terms used hereinhave the same meaning as commonly understood by one of ordinary skill inthe art to which this technology belongs. Although any methods andmaterials similar or equivalent to those described herein can also beused in the practice or testing of the present technology, a limitednumber of the exemplary methods and materials are described herein.

When a particular material is identified as being used to construct acomponent, obvious alternative materials with similar properties may beused as a substitute. Furthermore, unless specified to the contrary, anyand all components herein described are understood to be capable ofbeing manufactured and, as such, may be manufactured together orseparately.

It must be noted that as used herein and in the appended claims, thesingular forms “a”, “an”, and “the” include their plural equivalents,unless the context clearly dictates otherwise.

All publications mentioned herein are incorporated herein by referencein their entirety to disclose and describe the methods and/or materialswhich are the subject of those publications. The publications discussedherein are provided solely for their disclosure prior to the filing dateof the present application. Nothing herein is to be construed as anadmission that the present technology is not entitled to antedate suchpublication by virtue of prior invention. Further, the dates ofpublication provided may be different from the actual publication dates,which may need to be independently confirmed.

The terms “comprises” and “comprising” should be interpreted asreferring to elements, components, or steps in a non-exclusive manner,indicating that the referenced elements, components, or steps may bepresent, or utilized, or combined with other elements, components, orsteps that are not expressly referenced.

The subject headings used in the detailed description are included onlyfor the ease of reference of the reader and should not be used to limitthe subject matter found throughout the disclosure or the claims. Thesubject headings should not be used in construing the scope of theclaims or the claim limitations.

Although the technology herein has been described with reference toparticular examples, it is to be understood that these examples aremerely illustrative of the principles and applications of thetechnology. In some instances, the terminology and symbols may implyspecific details that are not required to practice the technology. Forexample, although the terms “first” and “second” may be used, unlessotherwise specified, they are not intended to indicate any order but maybe utilised to distinguish between distinct elements. Furthermore,although process steps in the methodologies may be described orillustrated in an order, such an ordering is not required. Those skilledin the art will recognize that such ordering may be modified and/oraspects thereof may be conducted concurrently or even synchronously.

It is therefore to be understood that numerous modifications may be madeto the illustrative examples and that other arrangements may be devisedwithout departing from the spirit and scope of the technology.

5.9 Reference Signs List

1000 patient 1100 bed partner 3000 patient interface 3100 seal-formingstructure 3102 sealing layer 3104 base 3106 naso-labial sulcusengagement area 3107 flanges 3108 first naris opening 3109 saddle region3110 second naris opening 3111 height 3112 mold 3114 accommodatingportion 3116 textile sheet 3117 pre-cut sheet 3118 membrane layer 3120notches 3122 notch 3124 first flap 3126 second flap 3150 cushionassembly 3152 frame 3154 assembly connection port 3155 assemblyconnection port 3200 plenum chamber 3300 stabilizing structure 3302 leftarm 3304 right arm 3306 end point 3308 first area 3310 second area 3312joint 3314 arm support 3322 contacting layer 3346 tab 3348 air deliverytube 3350 tube 3352 inner layer 3354 outer layer 3356 interior surface3358 interior surface 3360 textile sheet 3362 textile membrane 3363 tube3364 tube sheet 3366 outer covering 3368 textile membrane 3370 textilemembrane 3372 air passage 3374 exterior surface 3376 exterior surface3378 outermost portion 3380 outermost portion 3382 laser 3420 head strap3422 inner layer 3424 membrane layer 3426 outer layer 3428 firstdistance 3430 second distance 3432 head strap 3434 tube 3436 patientinterface 3437 interior layer 3438 exterior layer 3439 strap 3440 strap3441 strap 3442 strap 3443 pad 3450 tube 3452 inner textile layer 3454outer textile layer 3456 foam layer 3600 connection port 3602 uppersurface 3604 lower surface 3606 channel 3608 intake 3700 foreheadsupport 3701 connection port 3702 inner portion 3704 outer portion 3706support 3800 mold 3802 mold 3804 accommodating portion 4000 RPT device4010 external housing 4012 upper portion 4014 lower portion 4015 panel4016 chassis 4018 handle 4020 pneumatic block 4100 pneumatic components4110 air filter 4112 inlet air filter 4114 outlet air filter 4120muffler 4122 inlet muffler 4124 outlet muffler 4140 pressure generator4142 controllable blower 4144 brushless DC motor 4160 anti-spillbackvalve 4170 air circuit 4180 supplemental oxygen 4200 electricalcomponents 4202 printed circuit board assembly (PCBA) 4210 electricalpower supply 4220 input devices 4230 central controller 4232 clock 4240therapy device controller 4250 protection circuits 4260 memory 4270transducers 4272 pressure sensors 4274 flow rate sensors 4276 Motorspeed transducer 4280 data communication interface 4282 remote externalcommunication network 4284 local external communication network 4286remote external device 4288 local external device 4290 output devices4292 display driver 4294 display 4300 algorithms 5000 humidifier 5002humidifier inlet 5004 humidifier outlet 5006 humidifier base 5110humidifier reservoir 5120 conductive portion 5130 humidifier reservoirdock 5135 locking lever 5150 water level indicator 5240 heating element5600 conduit 5601 outer textile portion 5602 inner textile portion 5603impermeable layer 5604 passage 5605 joint 5610 elongate, tubular textileportion 6000 patient interface 6100 vent 6348 air delivery tube 7000patient interface 7200 hub 7220 elbow 7230 swivel connector 7300positioning and stabilising structure 7302 left arm 7303 connector 7304right arm 7306 notch 7308 chamfered edge 7309 slot 7312 upper connector7314 lower connector 7352 inner layer 7354 outer layer 7350 tube 7402outer covering 7404 adhesive layer 7406 outer cushioning layer 7408adhesive layer 7410 textile membrane 7222 textile sheet 7224 adhesivelayer 7226 inner cushioning layer 7228 adhesive layer 7230 textilemembrane 8000 patient interface 8300 positioning and stabilisingstructure 8302 left arm 8304 right arm 8350 tube 8362 lower portion 8364upper portion 9000 Patient interface 9100 Sealing or seal-formingstructure 9150 Cushion module 9200 Plenum chamber 9300 Positioning andstabilising structure/headgear 9304 Superior tube portion 9305 First endof the superior tube portion 9306 Second end of the superior tubeportion 9310 Strap 9313 Split 9320 Tab 9322 Slit 9324 Eyelet rigidiserportion 9331 Anterior edge 9332 Posterior edge 9348 Patient contactingportion 9349 Non-patient contacting portion 9350 Gas delivery tubes 9351Headgear tube connector 9352 Seam 9353 Seal portion 9357 Cushion moduleconnection port 9360 Crown Connector 9361 Crown connector port 9362Sealing flange 9363 Inferior tube portion 9365 Crown connector tubeportion 9371 First outer layer 9372 First adhesive layer of thenon-patient contacting portion 9373 Intermediate layer of thenon-patient contacting portion 9374 Second adhesive layer of thenon-patient contacting portion 9375 First inner layer 9381 Second outerlayer 9382 First adhesive layer of the patient contacting portion 9383Intermediate layer of the patient contacting portion 9384 Secondadhesive layer of the patient contacting portion 9385 Second inner layer9390 Fluid connection opening 9400 Vent 9410 Vent module opening 9600Connection port 9610 Elbow 9612 Conduit connector 9614 Swivel ring 9616Short tube 10000 Patient interface D1 direction D2 direction T tensileforce V1 first volume V2 second volume W1 first width W2 second width X1zone X2 zone X3 zone X4 zone

1-42. (canceled)
 43. A patient interface comprising: a plenum chamberpressurisable to a therapeutic pressure of at least 6 cmH2O aboveambient air pressure, said plenum chamber including a plenum chamberinlet port sized and structured to receive a flow of air at thetherapeutic pressure for breathing by a patient, a seal-formingstructure constructed and arranged to form a seal with a region of thepatient's face surrounding an entrance to the patient's airways, saidseal-forming structure having a hole therein such that the flow of airat said therapeutic pressure is delivered to at least an entrance to thepatient's nares, the seal-forming structure constructed and arranged tomaintain said therapeutic pressure in the plenum chamber throughout thepatient's respiratory cycle in use; a positioning and stabilisingstructure to provide a force to hold the seal-forming structure in atherapeutically effective position on a head of a patient, thepositioning and stabilising structure comprising: at least one gasdelivery tube to deliver the flow of air to the entrance of thepatient's airways via the seal-forming structure, the at least one gasdelivery tube being constructed and arranged to contact, in use, atleast a region of the patient's head superior to an otobasion superiorof the patient's head; and wherein the at least one gas delivery tubeincludes: an elongate, tubular textile portion having an exteriorsurface and an interior surface; and an impermeable layer comprising asingle, homogeneous piece of material joined to the interior surface ofthe elongate, tubular textile portion by blow molding such that theimpermeable layer is circumferentially continuous.
 44. The patientinterface according to claim 43, wherein the elongate, tubular textileportion is constructed from an outer textile portion and an innertextile portion that are connected by joints.
 45. The patient interfaceaccording to claim 44, wherein the inner textile portion has asubstantially planar cross-sectional shape, wherein the outer textileportion has a pre-determined non-planar cross-sectional shape, andwherein the outer textile portion is resilient such that when subjectedto external force the cross-sectional shape of the outer textile portionis altered, and when the external force is released the outer textileportion returns to the pre-determined non-planar cross-sectional shape.46. The patient interface according to claim 45, wherein the outertextile portion is constructed from a conformable material, and whereinthe conformable material is thermoformed to the non-planarcross-sectional shape.
 47. The patient interface according to claim 44,wherein the inner textile portion has different material properties thanthe outer textile portion.
 48. The patient interface according to claim44, wherein the inner textile portion is secured to the outer textileportion such that the outer textile portion imparts tension onto theinner textile portion.
 49. The patient interface according to claim 44,wherein the inner textile portion is joined to the outer textile portionat the joint such that a width of the joint is varied along a length ofthe at least one gas delivery tube.
 50. The patient interface accordingto claim 44, wherein the interior surface of the outer textile portionhas a positive curvature.
 51. The patient interface according to claim44, wherein the inner textile portion has a zero curvature.
 52. Thepatient interface according to claim 44, wherein the inner textileportion and the outer textile portion are joined together withoutstitching.
 53. The patient interface according to claim 44, wherein,during use, the at least one gas delivery tube is constructed andarranged such that pressurized air expands the inner textile portionaway from the outer textile portion.
 54. The patient interface accordingto claim 43, wherein the elongate, tubular textile portion isconstructed from a single, continuous piece of textile.
 55. The patientinterface according to claim 43, wherein the elongate, tubular textileportion formed by weaving.
 56. The patient interface according to claim43, wherein the elongate, tubular textile portion formed by knitting.57. The patient interface according to claim 43, wherein the elongate,tubular textile portion is constructed from a non-woven fabric.
 58. Thepatient interface according to claim 43, wherein the impermeable layeris joined to the interior surface of the elongate, tubular textileportion with a mechanical connection.
 59. The patient interfaceaccording to claim 43, wherein the impermeable layer is joined to theinterior surface of the elongate, tubular textile portion with achemical bond.
 60. The patient interface according to claim 43, whereinthe elongate, tubular textile portion comprises synthetic fibers. 61.The patient interface according to claim 60, wherein the syntheticfibers are nylon.
 62. The patient interface according to claim 60,wherein the synthetic fibers are polyester.
 63. The patient interfaceaccording to claim 43, wherein the impermeable layer is formed from apolymer.
 64. The patient interface according to claim 63, wherein thepolymer is one of: Liquid Silicone Rubber (LSR), Low DensityPolyethylene (LDPE), High Density Polyethylene (HDPE), PolyethyleneTerephtalate (PET), Polypropylene (PP), and Polyvinyl Chloride (PVC).65. The patient interface according to claim 43, wherein the exteriorsurface has a curved, non-patient contacting side and a substantiallyflat patient contacting side.
 66. The patient interface according toclaim 43, wherein the elongate, tubular textile portion has anoval-shaped cross-section.
 67. The patient interface according to claim43, wherein the elongate, tubular textile portion has a circularcross-section.
 68. The patient interface according to claim 43, whereinthe at least one gas delivery tube is constructed without any seamsextending from the exterior surface.
 69. The patient interface accordingto claim 43, wherein the thickness of the impermeable layer issubstantially consistent.
 70. The patient interface according to claim43, wherein the thickness of the impermeable layer varies in a directionparallel to the elongate, tubular textile portion's longitudinal axis.71. The patient interface according to claim 43, wherein the thicknessof the impermeable layer varies radially.
 72. The patient interfaceaccording to claim 43, wherein, in use, the at least one gas deliverytube is configured to extend continuously from a right side of thepatient's head, along the parietal bone, to a left side of the patient'shead.
 73. The patient interface according to claim 43, furthercomprising two gas delivery tubes, each configured to be positionedagainst a corresponding lateral side of the patient's head in use. 74.The patient interface according to claim 43, wherein the at least onegas delivery tube is thermoformed in a predetermined shape such that afirst arm extends along a first plane, and an upper portion extendsalong a second plane that is substantially orthogonal to the first planewithout external force or pressure.